Mahesh

These AP 7th Class Science Important Questions and 13th Lesson Wastewater Story Class 7 Extra Questions will help students prepare well for the exams.

Class 7 Science Wastewater Story Extra Questions

Wastewater Story Class 7 Important Questions

Question 1.
Write the different sources of wastewater?
Answer:
Different sources of wastewater are household activities, industrial activities and agricultural activities.

Question 2.
Why are manhioles built?
Answer:
Manholes are built as an access point to enable easy maintenance of the underground network of sewers if required.

Question 3.
What is sewerage?
Answer:
It is like a transport system that carries sewage from the point of being produced to the point of disposal, i.e., treatment plant.

Question 4.
What is cleaning of water?
Answer:
Cleaning of water is a process of removing pollutants before it enters a water body or is reused. This process of wastewater treatment is commonly known as “Sewage Treatment”. It takes place in several stages.

Question 5.
What do you mean by sewers?
Answer:
Sewers are the pipes acting as a transport system that carries sewage from point of origin to the point of disposal.

Question 6.
Which instrument is used to remove floatable solids from the wastewater?
Answer:
A skimmer is used to remove floatable impurities.

Question 7.
Why is ozone and chlorine used?
Answer:
Ozone and Chlorine is used to kill the bacteria etc., present in the clarified water.

Question 8.
What is the purpose of bar screens?
Answer:
Bar screens are used for the removal of large suspended objects in the wastewater such as plastics, cloth, rags, sticks, cans, etc.

Question 9.
Name two inorganic impurities present in sewage.
Answer:
Inorganic impurities present in sewage are nitrates and phosphates.

Question 10.
Why open drains is a concern?
Answer:
Open drain is a big concern for the society because they create unhygienic conditions and flies, mosquitoes and other insects breed can spread a number of diseases.

Question 11.
What is the dried sludge?
Answer:
Dried sludge is used as manure, thus returning organic matter and nutrients to the soil.

Question 12.
What helps to clean the clarified water?
Answer:
Aerobic bacteria helps to clean the clarified water.

Question 13.
What is activated sludge?
Answer:
The sludge collected at the bottom of the aeration tank (where clarified water is aerated) is called activated sludge.

Question 14.
Name any two things that can be made from the sludge extracted during the treatment of sewage.
Answer:
Biogas and manure are the things that can be made from the sludge extracted during the treatment of sewage.

Question 15.
What do you mean by sanitation?
Answer:
Sanitation is the proper disposal of sewage and garbage away from houses and surrounding areas.

Wastewater Story Extra Questions

Question 1.
What is sewage? Why we should plant eucalyptus trees all along sewage ponds?
Answer:
Sewage is a liquid waste which causes water and soil pollution. We should plant eucalyptus trees all along sewage ponds because these trees absorb all surplus wastewater rapidly and release pure water vapour into the atmosphere.

Question 2.
How are open drains harmful for human health?
Answer:
Open drains harmful for human health for the following reasons:

• It creates the most unhygienic and unsanitary conditions in its neighbourhood.
• It have foul smell and by that they cause air pollution.
• They are breeding places for flies, mosquitoes and other disease causing organism.

Question 3.
How is sewage is treated in industries?
Answer:
In industries, sewage is treated by an efficient treatment plant. These plants are specially designed to remove industrial waste for its reuse and safe release into the environment.

Question 4.
What is Vermi-processing toilet ?
Answer:
Vermi- processing toilet is a design of a toilet in which human excreta is treated by earthworms. It has been found to be a novel, low water use toilet for safe processing of human waste. The operation of the toilet is very simple and hygienic. The human excreta is completely converted to vermi cakes resource much needed for soil.

Question 5.
How is sludge treated?
Answer:
Sludge is the solid impurities separated from the sewage. It is removed and treated in a separate tank with anaerobic bacteria. During this process biogas is produced which is used to produce electricity. Dried sludge is used as manure.

Question 6.
How is water polluted?
Answer:
Water is used for various purposes in homes, industries and agriculture. When water is used for cleaning, bathing, washing, dying etc., it pollutes the water. Unwanted waste materials and chemicals etc. get added in the water and this wastes the water.

Question 7.
List some applications of water.
Answer:
Applications of water :

• Drinking and cooking.
• Washing and cleaning.
• Industrial use i.e., chemical industries.
• Irrigation in agriculture.
• In-car radiators to keep it cool.
• In water coolers to increase the moisture and coolness of surrounding air.

Question 8.
How kitchen waste blocks the drain ?
Answer:
Cooking oil that drain from kitchen into the pipes, hardens and blocks the pipes. The oil in open drains clogs the soil pores thereby preventing the filtration process and its effectiveness. It further hampers for the gradation process.

Question 9.
Why sanitation is must necessary at public places?
Answer:
Railway stations, bus depots, airports, hospitals are very busy places. Thousands of people visit them daily. Large amount of waste is generated there. It must be disposed of properly otherwise epidemics could break out.

Question 10.
How “bar screen” and ‘grit and sand removal tank’ help in clarification of water?
Answer:
When wastewater is passed through bar screens it separates big and large objects like plastics, bags, sticks, can, napkins etc–In grit and sand removal tank other solid impurities like pebbles etc., are removed.

Question 11.
How is excreta used as a source of cooking gas ?
Answer:
The anaerobic decomposition process of excreta as well as other organic matter such as kitchen waste results in the production of biogas, which can be supplied to homes and used as a means of cooking fuel or cooking gas.

Question 12.
Write short notes on septic tank and chemical toilets.
Answer:
Septic tank : Septic tanks are suitable for places such as hospitals, isolated buildings and clusters of houses where there is no sewage. Local governments or private corporations usually provide septic tanks in areas that have no direct connection to main sewage pipes. The septic tank system consists of a small sewage treatment system. Aeroplanes and trains usually have chemical toilets.

Chemical toilets: A chemical toilet uses chemicals to disinfect human waste and remove its bad odour. That is why trains and aeroplanes do not have elaborate plumbs and sewage.

Question 13.
Why bacteria are used in sewage treatment plants ?
Answer:
The bacteria decompose the suspended waste that includes domestic wastes and other undesirable organic substances present in the clarified water. The activity of bacteria produces decomposed organic material from which solid waste is separated. This solid waste is used as manure.

Question 14.
List the sequence involved in the treatment of wastewater in a WWTP.
Answer:
Steps in the treatment of wastewater :

• Passing through bar screens.
• Sedimentation of sand, grit, and pebbles.
• Removal of sludge and skimming of surface oil or floating substances.
• Decomposition of sludge for production of biogas.
• Production of clarified water.
• Aeration of clarified water.

Question 15.
What is the need to chloride any water supply? Name two other methods which help to do the same.
Answer:
For making water safe for drinking, chlorination can be done. In this process, chlorine tablets, bleaching powder or alum, added to water to prevent it from diseases. Filtration of sedimentatipri can also be done in order to make the water safe for drinking.

Extra Questions of Wastewater Story Class 7

Question 1.
How defection in open cause health hazards?
Answer:
Due to lack of proper sewage disposal system a large amount of people in India defecates in open. They use riverbeds, railway lines, fields and drains for this purpose. These excreta dries down and percolate, in soil with rain water. It pollutes the ground water. Excrete along river bed pollutes the river water. In this way water on the ground and under the ground get polluted. This polluted water contains the micro-organisms of various communicable diseases like cholera, typhoid, hepatitis and meningitis and dysentery etc.

Question 2.
What is the composition of sewage ?
Answer:
Sewage is a complex mixture containing suspended solids, organic and inorganic impurities, nutrients, saprotrophic and disease causing bacteria and other microbes.

• Organic impurities : Human feces, animal waste, oil, urea (urine), pesticide a herbicides, fruit and vegetable waste, etc.
• Inorganic impurities : Nitrates, phosphates, metals. Nutrients phosphorus and nitrogen.
• Bacteria : Such as which cause cholera and typhoid.
• Other microbes: Such as which cause dysentery.

Question 3.
Why is the period from 2005 to 2015 considered important in relation to the significance of water?
Answer:
The decade is considered the International Decade for action on “water for life”. It increased awareness about the need for better management of water as many parts of the world are in severe water crises. Water being essential for many life activities, this period saw a significant increase in awareness among the people regarding the importance and conservation strategies.

Question 4.
Describe various steps of cleaning wastewater in a wastewater treatment plant.
Answer:
The various steps are:

• Wastewater is passed through bar screens. Large objects like rags, sticks, cans, plastic packets, napkins are removed.
• Water then goes to a grit and sand removal tank. The speed of the incoming wastewater is decreased to allow sand, grit and pebbles to settle down.
• The water is then allowed to settle in a large tank which is sloped towards the middle. Solids like faeces settle at the bottom and are removed with a scraper. A skimmer removes the floatable solids like oil and grease. Water so cleared is called clarified water.
• Air is pumped into the clarified water to help aerobic bacteria to grow. Bacteria consume human waste, food waste, soaps and other unwanted matter still remaining in clarified water.

Question 5.
What is a septic tank? How does it function?
Answer:
Septic tank is a low cost on-site sewage disposal system. Septic tanks are suitable where there is no sewerage system for hospitals, isolated buildings or a cluster of four to five houses. Septic tank needs cleaning every four to six months.

Septic tanks serve three functions:
a) Removal of solids: As sewage enters the septic tank, its rate of flow is reduced to that the larger solids the sink to the bottom and soaps, grease and smaller solids rise to the surface. These solids’ are retained in the tank and the clarified effluent with suspended dissolved solids is discharged.

b) Bacterial action : The solids and liquids in the tank are partially decomposed by the bacteria and other natural process. These bacteria are called anaerobic because they thrive in the absence of free oxygen. This is the composition of sewage under anaerobic conditions is termed “septic”, hence the name of the system (and the cause of the odour).

c) Sludge and scum storage : Sludge is the accumulation of solids at the bottom of the time, his company is a partially submerged mat of floating solids that may form at or near the surface. Space must exist in the tank to store these residues during the interval between pumping.

Otherwise, the sludge and the scum will eventually be scoured from the tank and will clog the leaching field and receiving soil. The final stage of disposal : The treated effluent from the septic tank is discharged to the leach field where it percolates suitable “specific stone” and finally into the subsoil for further purification.

Question 6.
Write some consequences of the malfunctioning of sewage.
Answer:
Consequences of the malfunctioning of sewage are:

• Rupture or blockage or leakage of sewerage lines.
• Sewerage may overflow on the roads on the streets, creating poor sanitary conditions.
• It may set up the ecological balance in lakes and rivers.
• Water will become unfit for drinking and other domestic uses.
• The place may stink and become breeding ground for mosquitoes, flies etc.

Case Based / Data – Based Questions

Sewage is wastewater released by homes, industries, hospitals, offices and other users. It also includes rainwater that has run down the street during a storm or heavy rain. The water that washes off roads and rooftops carries harmful substances with it. Sewage is a liquid waste. Most of it is water, which has dissolved and suspended impurities.

In a home or a public building generally one set of pipes brings clean water and another set of pipes takes away wastewater. Imagine that we could see through the ground. We would see a network of big and small pipes, called sewers, forming the sewerage. It is like a transport system that carries sewage from the point of being produced to the point of disposal, i.e., treatment plant.

a) Manholes are located at how much distance in the sewerage?
Answer: Manholes are located at every 50 m to 60 m in the sewerage, at the junction of two or more sewers and at points where there is a change in direction.

b) Where does the sewers transports the sewage after collecting all the wastewater from various sources?
Answer: Sewers is like a transport system that carries sewage from the point of being produced to the point of disposal, i.e., treatment plant.

c) Define sewers.
Answer: The network of small pipes and big pipes which transports the sewage to treatment plant is called as sewers.

d) Sewage is released by whom?
Answer: Sewage is wastewater released by homes, industries, hospitals, offices and other users.

These AP 7th Class Science Important Questions and 8th Lesson Forests Our Lifeline Class 7 Extra Questions will help students prepare well for the exams.

Class 7 Science Forests Our Lifeline Extra Questions

Forests Our Lifeline Class 7 Important Questions

Question 1.
What do you mean by forest?
Answer:
Forest is a place hosting a number of animals and plants.

Question 2.
Paheli wrote a food chain in the following way:
Frog → Eagle → Insects → Grass → Snake
The chain is not in the correct order. Help her to write the food chain correctly.
Answer:
The correct food chain is:
Grass → Insects → Frog → Snake → Eagle
An insect eats green plant or grass – a frog eats the insects – the frog is eaten by snake – the snake is eaten by an eagle.

Question 3.
Define canopy.
Answer:
The uppermost branches and leaves of tall trees which act as a roof over the forest ground is called canopy. It is the highest layer of vegetation in the forest.

Question 4.
What are producers?
Answer:
Green plants are called procedures.

Question 5.
What is humus?
Answer:
Humus is a dark coloured substance which is formed from the dead bodies of plants and animals.

Question 6.
Define the crown of the tree.
Answer:
The branch part of a tree above the stem is known as the crown of the tree.

Question 7.
What do mean by deforestation?
Answer:
The cutting down and destroying of forests trees for personal as wells for commercial purpose is called deforestation.

Question 8.
What do you mean by afforestation?
Answer:
Planting more trees is called afforestation.

Question 9.
What are the animals lived in the deeper areas of the forest?
Answer:
Animals like boar, bison, jackals, porcupine, elephants live in the deeper areas of the forest.

Question 10.
What are carnivores ?
Answer:
The organisms which eat flesh and are dependent on other animals for food are called carnivores.

Question 11.
Write any three things we get from forests?
Answer:
Gum, medicine and wood are the products we get from forests.

Question 12.
Name some factors responsible for clearing of forests.
Answer:
Construction of roads and buildings, increase in demand for wood industrial development, etc.

Question 13.
What do you mean by food chain? Give an example.
Answer:
The process of food transfer from plants through a series of organisms. The chain of eating and being eating is known as a food chain.
Example : Grașs → Insects → Frog →Snake → Eagle

Question 14.
In which layer of the soil would you find in humus? What is its importance to the soil?
Answer:
Humus are found in the top, organic layer of soil. It provides many useful nutrients to the soil.

Question 15.
Why is the forest’s floor dark in colour?
Answer:
The forest floor is dark in colour because of the decompositions of animal and plant matter into dark-coloured humus.

Forests Our Lifeline Extra Questions

Question 1.
Deforestation may lead to floods. Why?
Answer:
Deforestation leads to floods because as lesser number of trees will be available due to the deforestation. In the absence of trees and plants of the forest, the excessive amount of rainwater falling during heavy rains cannot be absorbed into forest ground. The large amount of rainwater will then suddenly flow into rivers causing the flooding of rivers.

Question 2.
Why are forests called dynamic living entity ?
Answer:
Forests are called a dynamic living entity because everything that resides within it plants or animals are in dynamic equilibrium. The food chain is in continuous function and all that is produced hence is returned to the soil.

Question 3.
How are forests useful to us ?
Answer:
The forests are very useful to us in the following ways :

• They conserve soil and water.
• They are helpful in causing rains.
• They give us food and fruit.
• They are the natural habitats of animals.
• They help in the maintenance of ecological balance.

Question 4.
Define understoreys.
Answer:
The trees in the forest had crown of different types and sizes. These had created different horizontal layer known as understoreys. Giant and the tall trees constituted the top layer followed by shrubs and tall grasses and herbs formed the lowest layer.

Question 5.
Why forests are called as green lungs ?
Answer:
All the green plants absorb carbon dioxide for photosynthesis and release oxygen to the atmosphere. Thus they had to maintain the balance in oxygen and carbon dioxide level in aid. So the forests are called green lungs.

Question 6.
How do forest maintain the water cycle ?
Answer:
The role of forests in the water cycle is to add water to the atmosphere through the process of transpiration (in which plants release water from their leaves during photosynthesis). This moisture contributes to the formation of rain clouds which release the water back onto the forests. This maintains the water cycle and water level in the environment.

Question 7.
How can soil erosion be prevented ?
Answer:
Soil erosion can be prevented by planting more trees, as the roots of trees help to bind the soil and prevent it from being carried away by the rainwater.

Question 8.
Write about the dependence of plants on animals?
Answer:
Dependence of plants on animals :

• Animals produce carbon dioxide during respiration which is released in the atmosphere. Plants use this oxygen for preparing food.
• A number of insects, birds and bats help in pollination.
• Some animals help in dispersal of fruits and seeds.

Question 9.
Plants are known as the producers of a food chain. Give reason.
Answer:
Plants are known as the producers of a food chain. It is because green plants (autotrophs) make their own food from carbon dioxide and water in the presence of sunlight and chlorophyll by a process called photosynthesis and provide food to all living organisms which live in the forest.

Question 10.
What happens if an animal dies in the forest?
Answer:
The dead animals become food for vultures, crows, jackal and insects and in this way nutrients are cycled, thus we say nothing goes waste in forest.

Question 11.
Differentiate between humus and decomposers.
Answer:
Humus is a dark-brown or black organic substance made up of decayed plant or animal matter. Humus provides nutrients for plants and increases the ability of soil to retain water. But decomposers are the microorganisms that convert the dead plants and animals to humus.

Question 12.
How are the nutrients of the soil related to decomposers?
Answer:
Different plants and animals lives in forest. When they die, nobody cremates their dead bodies. They keep on lying there. Scavengers like vultures, eagles etc., eat their dead bodies. They eat flesh and other soft organs. The rest of the dead bodies are broken and down by various microorganisms are called decomposers. They decompose the dead bodies of plants and animals into a dark substance called humus which maintains the nutrient level of the soil.

Extra Questions of Forests Our Lifeline Class 7

Question 1.
What are the various ways we take to conserve our forests?
Answer:
Some of the ways to conserve forests are:

• Excessive cutting down of forest trees should not be allowed by the government to conserve forests.
• More trees should be planted in the forest in place of cut down trees to conserve forests.
• Paper products such as old newspapers, magazines, books, notebooks, etc., should be recycled to conserve forests.
• Awareness programmes should be conducted to educate the public about the importance of afforestation.
• An area should be defined to graze domestic animals so that they don’t damage assets of forest.
• Discourage the use of wooden furniture.
• Impose strict environmental laws.

Question 2.
What will happen if forest disappear?
Answer:
The consequences if forest disappears are as follows :

• Soil erosion will increase which will affect soil fertility and productivity.
• Air pollution will increase which will ultimately threaten thirty existence of life on the Earth.
• Unpredictable changes will take place in weather and climate,
• Reduction in rainfall.
• Reduction in recharging of existing water resources
• Wildlife may also disappear along with forest.
• Shortage of forest products.
• Disturbance in ecological balance.
• Increase in temperature
• Global warming may reach in flooding of low lying area.

Question 3.
Why are forests called the green lungs of a city?
Answer:
Forests are called the ‘green lungs of a city because just like lungs exchange gases, they also do the same. They maintain the balance between carbon dioxide and oxygen in the environment by their dual processes i.e., photosynthesis and respiration. They absorb carbon dioxide from the environment and produce oxygen that we all breathe in. Hence, they are called green lungs.

Question 4.
Write the uses of forests?
Answer:
Forests are useful to us for the following reasons:

• Forests provide timber for building and furniture.
• Forests keep the environment cool and increase the chances of rainfall.
• The roots of the trees hold the soil firmly thereby checking soil erosion.
• Forests provide habitat to a variety of wild plants and animals.
• The plants of forests use CO₂ and release oxygen in photosynthesis, thereby maintaining balance of gases in atmosphere.
• Forests provide animal products such as honey, lac, wax, etc.
• Forests provide plant products such as fruits, nuts, gums, resins, fibres, medicines, essential oil (like sandal wood), etc.
• They are involved in the absorption of water which percolates in the soil, thereby becoming a part of the groundwater.

Question 5.
Forests are valuable resources. Explain.
Answer:
Forest products play vital role in socio-economic development. We get food (cereals, pulses and fruits), fire wood, fibre, construction material, industrial products (tannins, lubricants, dyes, resins and perfumes) and products of medicinal importance. It is also the home of diverse wildlife which maintains the ecosystem.

Forests give oxygen to keep us alive and absorb carbon dioxide and it also help in maintaining water cycle in nature. Forests save the soil from erosion and help in maintaining the ground water level.Thus, forests are valuable resources:

Question 6.
All the needs of animals living in a forest are fulfilled. Justify this statement in a few sentences.
Answer:
Forest provides home (shelter), food and water to the animals living there. There are a large number of various types of animals in the forest. The forests provide a natural habitat to animals. The different layers of regulation present in a forest provide food and shelter.

Forest provides leaves, flowers, fruits, seeds, nuts and bark of trees as food for herbivorous animals. The carnivorous animals hunt and eat herbivorous animals. The dense bushes, tall grasses and thick trees provides shelter and also protection for herbivorous animals.

Case Based/Data – Based Questions

Prof. Ahmad asked children to pickup leaves from the forest floor and observe them under a hand lens. They found tiny mushrooms over the decaying leaves. They also saw an army of tiny insects, millipedes, ants and beetle on them. They were wondering how these organisms live there. Prof. Ahmad explained that apart from these animals which are easily seen, there are several organisms and micro-organisms that live in the soil. Paheli wondered what mushroom and other micro-organisms eat. Prof. Ahmad replied that they feed upon the dead plant and animal tissues and convert them into a dark coloured substance called humus.

The micro-organisms which convert the dead plants and animals to humus are known as decomposers. These micro-organisms play an important role in the forest. Soon, Paheli removed some dead leaves and discovered under them a layer of humus on forest floor. The presence of humus ensures that the nutrients of the dead plants and animals are released into the soil. From there, these nutrients are again absorbed by the roots of the living plants. “What happens if an animal dies in the forest?”Sheila asked. Tibu replied the dead animals become food for vultures, crows, jackals and insects.” In this way, the nutrients are cycled. So, nothing goes waste in a forest.

i) Children observed the leaves with the help of.
a) Hand lens
b) Microscope
c) Torch
Answer:
a) Hand lens

ii) The nutrients in the soil are absorbed by which part of the plant?
Answer: The nutrients in the soil are absorbed by the roots.

iii) What are decomposers?
Answer: The organisms which derive their food from the dead and decaying animals or plants are called decomposers.

iv) What did the presence of humus ensures?
Answer: The presence of humus indicates that the nutrients from the dead and decaying organic matter are released in to the soil.

These AP 7th Class Science Important Questions and 11th Lesson Light Class 7 Extra Questions will help students prepare well for the exams.

Class 7 Science Light Extra Questions

Light Class 7 Important Questions

Question 1.
The image formed by a lens is always virtual, erect and smaller in size for an object kept at different positions in front of it. Identify nature of lens.
Answer:
The lens which always forms virtual, erect and smaller image in spite of the different positions of an object is called concave lens.

Question 2.
Define ‘Reflection’.
Answer:
Reflection is the bouncing back of a ray of light after striking a reflecting surface.

Question 3.
How does light travel from one point to the other?
Answer:
Light travel from one point to the other in straight line.

Question 4.
Define real image.
Answer:
The image which can be obtained on a screen is called a real image.

Question 5.
What is VIBGYOR?
Answer:
It represent the order of seven colours in the rainbow i.e., violet, Indigo, blue, green, yellow, orange and red.

Question 6.
What is virtual image?
Answer:
The image formed by a plane mirror cannot be captured on a screen, and is called a virtual image.

Question 7.
What is image of an object?
Answer:
Due to the reflection of light, the impression of an object formed in a mirror is called the image of the object.

Question 8.
What is the dispersion of light?
Answer:
The splitting of white light into seven colours is called dispersion of light.

Question 9.
What happens when light falls on abolished or a shiny surface?
Answer:
When light falls on a polished shiny surface, it gets reflected.

Question 10.
How can we change the path of light?
Answer:
We can change the path of light by keeping any shiny or polished or reflecting material in the path of the light beam.

Question 11.
What is concave mirror?
Answer:
The mirror whose reflecting surface is concave (and polished surface is convex) is called a concave mirror. It is also known as a converging mirror.

Question 12.
How can we change the direction of the light?
Answer:
We can change the direction of light by the phenomenon called reflection.

Question 13.
What is a lens?
Answer:
A lens is a piece of transparent medium bounded by two surfaces in which at least one has curved surface.

Question 14.
What is prism?
Answer:
Prism is a transparent glass pyramid bounded by four triangular surfaces that separates white colour into a spectrum of colours.

Question 15.
Is the image formed by a plane mirror is always upright?
Answer:
Yes, the image formed by the plane mirror is always upright.

Light Extra Questions

Question 1.
The concave reflecting surface of a torch got rusted. What effect would this have on the beam of light from the torch?
Answer:
If the concave reflecting surface of a torch got rusted, it will produce diffused beam of light with lower intensity.The objects will not be clearly visible in this diffused and lower intensity of light.

Question 2.
What type of mirror is used by the dentist and other doctors? Why?
Answer:
A concave mirror is used by doctors for examining eyes, ears, nose, and throat as it gives an enlarged view of the targeted object.

Question 3.
What do you mean by lateral inversion? Give a suitable example.
Answer:
When an object is placed in front of a plane mirror, then the right side of the object appears to be the left side of the image and the left side of the object appears to be the. right side of the object. This side of changes of an object and its mirror image is called lateral inversion. For example, the word ‘AMBULANCE’ on an ambulance is written in micro writing.

Question 4.
How is the rainbow formed?
Answer:
A rainbow is formed by the refraction and reflection of the sun’s rays through raindrops. When it is raining in one part of the sky and sunny in another, a rainbow appears. The centre of the rainbows arc is always directed away from the sun.

Question 5.
Draw concave and convex lens.
Answer:

Question 6.
The distance between an object and a convex lens is changing. It is noticed that the size of the image formed on a screen is decreasing. Is the object moving in a direction towards the lens or away from it?
Answer:
In case of convex lens, when we move the object away from the lens, the size of image decreases and ultimately, when object is at infinite distance a point image is formed at the focus of lens.

Question 7.
What are the spherical mirrors? Give their types.
Answer:
Mirrors having curved surfaces are known as spherical mirrors. Their name is so, because they are considered as a part of a hollow sphere.Mirrors are mainly of two types: concave mirrors and convex mirrors.

Concave mirrors: Its reflecting surface is curved inwards.
Convex mirrors: Its reflecting surface is bulged out.

Question 8.
State any two uses of convex lens.
Answer:
Two uses of convex lens are :

• Convex lens is used as magnifying glass.
• Convex lens is used in spectacles, camera, microscope, telescope and binoculars.
• Convex lens are used in telescope.

Question 9.
What happens when the light falls on the mirror?
Answer:
The mirror changes the direction of light that falls on it when light falls on the mirror it reflects back in a different direction.

Question 10.
What type of mirror is used as a side mirror in a scooter? Why is this type of mirror chosen?
Answer:
A convex mirror is used as a side mirror in scooters. This type of mirror is chosen as it forms a smaller and virtual image. So, it can be used to see a much larger area than the area visible by a plane mirror.

Question 11.
Why do we need a shiny surface for reflection?
Answer:
The extent of reflection depends upon the shine and smoothness of the surface. So, greater the shining and smoothness of the surface, greater will be the reflection. So, this is a reason why we require a shiny surface for reflection.

Question 12.
What did Newton demonstrate by his experiments with the prism?
Answer:
Newton demonstrated by his experiments with the prisms that white light consists of a mixture of seven colours.

Question 13.
Why a convex lens and a concave lens are called coverging lens and diverging lens respectively?
Answer:
A convex lens converger the light generally falling on it. Therefore it is called converging lens. On the other hand, a concave lens diverges the light and is called diverging lens.

Extra Questions of Light Class 7

Question 1.
You are given three mirrors of different types. How will you identify each one of them?
Answer:
We can identify the mirrors by forming images of an object which are given as below:

• Plane mirrors: In case of a plane mirror the image formed will be virtual, erect and of the same size as that of the object.
• Concave mirrors: In the case of a concave mirror the image formed may be virtual or real, erect or inverted, magnified or diminished depending upon the position of the object.
• Convex mirror : In the case of a convex mirror the image formed will always be virtual, erect, and diminished.

Question 2.
Explain Newton’s experiment by which he proved that white light is made up of light of seven colours.
Answer:
Newton’s experiment: The idea that sunlight consists of several colours was first put forward by Sir Isaac Newton. He passed a narrow beam of light into a prism. The light that emerged from the prism was found to be coloured as in a rainbow. He gave the name spectrum to this coloured A prism splits a beam of sunlight into seven colours patch of light.

The spectrum was seen to consist of seven colours of light – violet, indigo, blue, green, yellow, orange and red. The various colours found in white light can be easily remembered as VIBGYOR. The process of splitting up of white light into different colours is called dispersion of light.

Question 3.
What is a lens ? Describe the two types of lens and their role in our day to day life.
Answer:
A lens is a piece of any transparent glass bound by the two curved surfaces or by one curved and one plane surface.When light rays pass through a lens, they bend and change their direction.

There are two types of lens. They are : concave lens and convex lens.

Convex lenses: Convex lens is thick in the middle and thin at its edge. When light rays pass through a convex lens, they bend inwards and converge at a common point to form an image of the source of light. Rays from the sun converge to form its image as a bright spot. A convex lens converges light rays. Therefore, it is also called a converging lens.

The image formed when the object is placed close to a convex lens is virtual, , erect and magnified. Virtual images cannot be caught on a screen. Images that are caught on a screen are called real images. When the object is placed at a distance from a convex lens, the image formed is real, inverted and diminished.

Concave lens : Concave lens is thin at the centre and thicker at edge. It is a lens that possesses at least one surface that curves inwards. When light rays are incident on a concave lens, they bend outwards or diverge. The rays diverge away from each other. Thus, a concave lens is also called a diverging lens.

A concave lens is thinner at its centre than at its edges, and is used to correct short sightedness. It does not focus at a single point. The image formed by a concave lens is upright, virtual and smaller than the object. For example, the images seen through a peephole are different from normal holes, because these peep holes contain concave lenses.

Question 4.
What is the Newtons disc ? Why does it appear white when rotated ?
Answer:
A circular disc constructed by Newton which is divided into seven parts painted with seven colours is known as Newtons disc. The colours painted on disc are those of spectrum of visible light. When the disc is rotated fast, the colours get mixed together and the disc appears to be whitish.This appearance of white light on rotating disc suggests that white light consist of seven colours.

Question 5.
Differentiate between concave mirror and convex mirror.
Answer:
Differences between concave mirror and convex mirror are as follows :

S.No.	Concave mirror	Convex mirror
1)	Spherical mirrors whose inner side is reflecting are called concave mirrors.	Spherical mirrors whose outer side is reflecting are called convex mirrors.
2)	It can form real and virtual image.	It always form virtual image.
3)	It is also called converging mirror.	It is also called diverging mirror.
4)	It can form a magnified image.	It can form a diminished image.
5)	It can form both erect and inverted image.	It always forms an image.

Question 6.
Differentiate between real and virtual images.
Answer:
Difference between real and virtual images are as follows :

S.No.	Virtual image	Real image
1.	The image that can not be obtained on a screen is called a virtual image.	The image that can be obtained on a screen is called a real image.
2.	It is always erect.	It is always inverted.
3.	It is formed always behind the mirror.	It is obtained on the same side of mirror as the object.
4.	It’s formed by a plane mirror and concave lens.	It’s formed by a concave mirror and convex lens.
5.	Rays converge at a point to form the image.	Rays appear to diverge from a point where the image is formed.

Question 7.
How will you come to know that the mirror given to you is a concave or convex?
Answer:
In the concave surface the polish is done on its outer surface and the inner surface is shining. If we bring it closer to our face the later will look very big. In a convex mirror the polish is done on the inner surface and then outer side is shining. In this mirror our face will always appear to be shorter.

Question 8.
Write any two uses of concave mirror and convex mirror.
Answer:
Uses of concave mirror:

• They are used in reflected of car, head-lights and search lights.
• They are used as shaving mirrors.
• They are used by dentists to see an enlarged image of teeth.
• They are used in telescopes.

Uses of convex mirror:

• They are used in automobiles by the drivers for seeing the erect images of the,traffic.
• They are used as staircase mirrors on the double decker buses.
• They are used as rear view mirrors in automobiles such as buses, cars, scooters, trucks etc., to see the traffic coming from behind.

Case Based / Data – Based Questions

Priya’s sister, Shreya was preparing the dinner in her kitchen for Priya and her bother. Both of them were feeling so much hungry and they sat ideally on their respective chairs and having empty plates and spoons on their dinning table. They were shouting like a 5 years old child that they wanted the dinner so much eagerly in order to fulfil their stomach.

At the sometime, Priya’s sister observed the cooked food to both of them and the moment, when Priya was just about to eat the rice with the help of spoon, she noticed that the. spoon has such a shining surface that it reflected the light rays incident on it.

a) Explain the importance of shining surface in the reflection of light.
Answer: As we know that the extent of reflection depends upon the shining of surface. So, greater the shining of the surface, more will be the reflection.

b) Name the type of spherical mirror represented by the shining steel spoon.
Answer: Both convex and concave mirrors are represented by the shining steel spoon.

c) What do you mean by reflection?
Answer: Reflection is the bouncing back of a ray of light after striking a reflecting surface.

d) What type of mirror is represented by the backside of a shining steel spoon?
Answer: The backside of the steel spoon acts as a convex mirror (diverging mirror)

These AP 7th Class Science Important Questions and 10th Lesson Electric Current and its Effects Class 7 Extra Questions will help students prepare well for the exams.

Class 7 Science Electric Current and its Effects Extra Questions

Electric Current and its Effects Class 7 Important Questions

Question 1.
Why is an electric fuse required in all electrical appliand?
Answer:
Electric fuse is required in all electrical appliances to prevent damage from excessive current flow and during short circuit.

Question 2.
What do the long line and the shorter line in an electric cell represent?
Answer:
The longer line represents the positive terminal and the thicker, shorter line represents the negative terminal.

Question 3.
What is the coil of wire in electric devices known as?
Answer:
The coil of wire in electric devices is known as an element.

Question 4.
What are the components of a simple electric circuit?
Answer:
The components of a simple electric circuit are battery, wire, key and bulb.

Question 5.
What is an electric cell?
Answer:
It is a device which produces electric charge because of some chemical reactions.

Question 6.
Where does the needle of the compass point?
Answer:
The needle of the compass points in the North-South direction.

Question 7.
Name the scientist who noticed the magnetic effect of electric current for the first time.
Answer:
Hans Christian Oersted noticed the magnetic effect of electric current for the first time.

Question 8.
Which effect of electric current is utilised in the working of an electric fuse?
Answer:
An electric fuse works on the heating effect of current.

Question 9.
Expand MCB.
Answer:
The full form of MCB is “Miniature Circuit Breakers”

Question 10.
What is electromagnet? Name a device that uses electromagnet.
Answer:
A current carrying coil of an insulated wire wrapped around a piece of iron is called an electromagnet. Cranes uses electromagnet.

Question 11.
What is a circuit diagram?
Answer:
A circuit diagram is a graphical representation of an electric circuit which is the drawn using symbols of different electrical components.

Question 12.
What is a fuse?
Answer:
A fuse is a safety device which prevents the damage is to electrical circuits and possible fires.

Question 13.
On what factors does the heat produced in a wire depends?
Answer:
It depends on the material, length and thickness of wire.

Question 14.
Where can we place the key or switch in the electric circuit?
Answer:
We can place the key or switch anywhere in the circuit.

Question 15.
What do you mean by battery?
Answer:
It is a combination of two or more cells in which the positive terminal of one cell is connected to the negative terminal of the next cell is called a
battery.

Question 16.
What happens when we bring a magnet close to the compass?
Answer:
The needle of the compass shows deflection when we bring a magnet close to it.

Electric Current and its Effects Extra Questions

Question 1.
Name two electric devices for each where
a) heating effect of current is used and
b) magnetic effect of current is used.
Answer:
a) Heating effect of current is used in room heater and geyser.
b) Magnetic effect of current is used in electric bell and cranes.

Question 2.
Can we use the same fuse in a geyser and a television set? Explain.
Answer:
No, we cannot use the same fuse in a geyser and television because a geyser and a television set require a different amount of current. The fuse used in every appliance has some limit to withstand the current flowing through it. So, different appliances have fuses of different ratings.

Question 3.
What are the conditions necessary for an electric current to flow?
Answer:
The necessary conditions for an electric current to flow are as follows :

• A source of electric current (a cell or a battery).
• A conducting material or metal wire.
• An uninterrupted path for the flow of charge.

Question 4.
When does the current to flow through the circuit ? Explain.
Answer:
When the switch is in the on position, and the positive terminal of the battery is connected to the negative terminal of the battery through wires then the circuit is said to be closed and the current flows throughout the circuit.

Question 5.
What are the reasons for excessive currents ?
Answer:
The possible reasons for excessive currents are as follows :

• One reason for excessive currents in electrical circuits is the direct touching of wires. This may happen if the insulation on the wires has come off due to wear and tear.
• The connection of many devices to a single socket may cause overloading in the circuit and thus may lead to possible fires.

Question 6.
Write short notes on heating effects of electric current.
Answer:
When an electric current flows through a wire, the wire gets heated. It is the heating effect of current or when current flows through a metal wire it gets heated up, this is called heating effect of current. E.g: a glowing electric bulb becomes warm. This effect has many applications like Electric Heater, Light Bulb etc.

Question 7.
Give two methods by which we can increase the strength of magnetic field produced by a circular coil carrying current?
Answer:
The two methods by which we can increase the strength of magnetic field are as follow:

• By increasing the number of turns of wire in the coil.
• By increasing the current flowing through the coil.

Question 8.
Explain the formation and uses of battery.
Answer:
A combination of two or more cells in which the positive terminal of one cell is connected to the negative terminal of the next cell is called a battery. It supplies electric current. To identify the positive and negative terminals, they are denoted as + and – respectively. These batteries are used in many devices, such as torch lights, mobile phones, calculators and even automobiles.

Question 9.
Differentiate between an open and a closed circuit.
Answer:
Open circuit : The electric path which starts from positive terminal of a cell or battery but is broken at some point, is called an open electric circuit. Current does not flow from.such a circuit and the switch is in ‘OFF’ position.
Closed circuit : The electric path which starts from the positive terminal of a cell or battery ends at its negative terminal, without any break, is called a closed electric circuit. Current flows in the circuit and the switch is in ‘ON’ position.

Question 10.
Why do we generally represent an electric circuit by its circuit diagram?
Answer:
We generally represent an electric circuit by its circuit diagram because it is much easier to draw circuit diagrams using symbols.

Question 11.
Write the functions of an MCB.
Answer:
The functions of an MCB are :
We can use an MCB in place of a fuse. It automatically breaks the circuit if it crosses the safe limit of electricity and prevents short circuits and other damage. An MCB can be handled manually.

Question 12.
If the current flows through wire, does the wire behave like a magnet?
Answer:
When the current flows through any wire, a magnetic field is developed around that wire or coil and it behaves like magnet. It can be analysed by placing a magnetic compass around the wire, it will show deflection of the needle.

Question 13.
If we connect more cells in the circuit, then what will happen?
Answer:
If we connect more of cells in the circuit, then the nail will attract more pins. It is due to the reason that the current flowing through the wire wound on the nail will get increase which in turn will increase the strength of the electromagnet.

Question 14.
Write the differences between a bar magnet and electromagnet.
Answer:
The differences between bar magnet and a electromagnet are as follows :

S.No.	Electromagnet.	Permanent magnet
1)	It is usually made up of soft materials.	It is usually made up of hard materials.
2)	Removal of magnetic properties is temporary.	Once magnetic properties are lost, it becomes useless.
3)	The magnetic properties that are displayed when current is passed through it.	Magnetic properties exist even when no current is there.
4)	The poles of this kind of magnet can be altered with the flow of current.	The poles of this kind of magnet cannot be changed and are fixed.
5)	The strength is adjusted depending upon the amount of flow of current.	The strength depends upon the. nature of the material used in its creation.

Question 15.
On what does the strength of an electromagnet depend upon?
Answer:
The strength of an electromagnet depends upon the amount of current flowing through the coil and the number of turns of copper wire in the coil.

Extra Questions of Electric Current and its Effects Class 7

Question 1.
What are electric fuses? Why are they called safety devices?
Answer:
The wires made up of special materials which melt quickly and break when large electric currents are passed through them are known as electric fuses. There is a maximum limit of electric current that can safely flow through a circuit.

If by accident the current exceeds this safe limit, the wires may become overheated and may cause a fire. If a proper fuse is there in the circuit, it may blow off and break the circuit, thus preventing damage to electric circuits and possible fires. Thus, electric fuses are called safety devices.

Question 2.
What is electromagnet? Write various uses of the electromagnet.
Answer:
A core of magnetic material surrounded by a coil of wire behaves like a magnet when electric current flows through it. When the electric current is switched off, the coil generally losses its magnetism. Such coils are called electromagnet.
Various uses of the electromagnet are as follows:

• It is used in separating magnetic materials such as iron, nickel, and cobalt from the garbage heaps.
• It is used in making appliances such as electric bells, telephones, audio players, and recorders.
• It is used in taking out tiny pieces of magnetic material that have accidentally fallen in the eye.
• It is used in various toys.
• Bullet trains use the principle of electromagnetism.
• Audio and video tapes use the principle of electromagnetism.

Question 3.
What are the differences between electromagnet and permanent magnet?
Answer:
The differences between electromagnet and a permanent magnet are as follows :

S.No.	Electromagnet	Permanent magnet
1)	It is usually made up of soft materials.	It is usually made up of hard materials.
2)	Removal of magnetic properties is temporary.	Once magnetic properties are lost, it becomes useless.
3)	The magnetic properties that are displayed when current is passed through it.	Magnetic properties exist even when no current is there.
4)	The poles of this kind of magnet can be altered with the flow of current.	The poles of this kind of magnet cannot be changed and are fixed.
5)	The strength is adjusted depending upon the amount of flow of current.	The strength depends upon the nature of the material used in its creation.

Question 4.
Draw the symbols of the following circuit components.
a) electric cell
b) switch in OFF position
c) electric bulb
d) battery
Answer:

Question 5.
When the current is switched on through a wire, a compass needle kept nearby gets deflected from its north-south position. Explain.
Answer:
We know that the needle of a compass is a tiny magnet, which points in north-south direction. When we bring a magnet close to it, the needle gets deflected. Also, when an electric current flows through a wire, it produces magnetic effect around it. Therefore, when the current is switched on through a wire, a compass needle kept nearby gets deflected from its north-south position due to magnetic effect of electric current around the wire.

Question 6.
Write short notes on short circuiting and overloading.
Answer:
Short circuiting : Short-circuiting occurs in a circuit when the live wire comes in direct contact with the neutral wire. This causes much damage to the electric appliances connected with them.

Overloading: Overloading occurs in a circuit when the current in the circuit increases abruptly. It causes overheating of the wire and might lead to the fire. It can also occur due to accidental increase in the supply voltage or on connecting too many appliances to a single socket.

Question 7.
Explain the working of an electric bell.
Answer:
An electric bell consists of a coil of wire wrapped in an iron piece. It is connected to the source of current through a switch. It has a metallic gong, a hammer to strike the gong, and a contact screw attached to the iron strip. When the iron strip is in contact with the screw, the current flows through the coil which becomes an electromagnet.

It pulls the iron strip, in this process the hammer at the end of the strip strikes the gong of the bell to produce a sound. But when the electromagnet, pull the iron strip, it also breaks the circuit. The current through the coil stops flowing. The iron strip comes back to its original position and touches the contact screw. This completes the. circuit again and the process is repeated in quick succession and the bell rings

Case Based / Data – Based Questions.

Mohan saw her mother running microwave, oven, electric rice cooker, and mixer grinder from a single socket. He immediately rushed to his mother and remind her of overloading and its consequences. Mohan’s mother immediately turned off the switch and connected them one by one according to her needs. She felt very happy for Mohan for his presence of mind.

i) What is overloading?
Answer:
It can occur due to accidental increase in the supply voltage or on connecting too many appliances to a single socket.
(Or)
When excess amount of electric current passes through excessive heating takes place, this is called overloading.

ii) What is the full form of MCB?
Answer:
The full form of MCB is “Miniature Circuit Breakers”

iii) What are the consequences of overloading?
Answer:
The consequences are overloading it can damage the Circuit of house. It can also leads to fire.

iv) What role do MCB plays in case of overloading?
Answer:
When there is overloading of current, MCB trips and switches off, which in turn cut off the supply of electricity, and thus protect us from damages due to overloading of current.

These AP 7th Class Science Important Questions and 9th Lesson Motion and Time Class 7 Extra Questions will help students prepare well for the exams.

Class 7 Science Motion and Time Extra Questions

Motion and Time Class 7 Important Questions

Question 1.
A simple pendulum Is oscillating between two points A and B as shown In figure. Is the motion of the bob uniform or non-uniform?
Answer:
The motion of the bob is non-uniform because the speed of the bob keeps changing as it does not cover equal distance in equal intervals of time.

Question 2.
If Shyam covers a certain distance in one hour and Ram covers the same distance in two hours, who travels in a higher speed?
Answer:
Ram travels with a higher speed, as he has covered the same distance in lesser time than Shyam.

Question 3.
What is a motion?
Answer:
Motion is defined as there is a change in the position of an object with the time.

Question 4.
Define Speed.
Answer:
The distance travelled by an object in a unit time (either in one hour, in one minute or in one second) is known as speed of the object.
\(\text { Speed }=\frac{\text { Distance travellèd }}{\text { Time taken }}\)

Question 5.
Define time period.
Answer:
The time taken by the pendulum to complete one oscillation is called its time period

Question 6.
What is an oscillatory motion?
Answer:
The to and fro motion of an object is called oscillatory motion.

Question 7.
Give any two examples of periodic motion.
Answer:
Examples of periodic motion are :

• Rotation of earth on its axis.
• Moon moves around the earth.

Question 8.
What is the unit of speed?
Answer:
The unit of speed is meter per second.

Question 9.
What do you mean by uniform motion?
Answer:
An object moving along a straight line keeps changing, its motion is said to be non uniform motion.

Question 10.
What do you mean by non – uniform motion?
Answer:
An object moving along a straight line with a constant speed; in the motion is said to be uniform motion.

Question 11.
What is bob?
Answer:
The metallic ball is called bob of the pendulum.

Question 12.
What devices do we use to measure intervals of time which are much shorter than a day?
Answer:
The most common time measuring devices used are docks or watches.

Question 13.
What are the various types of graphs?
Answer:
The various types of graphs are pie chart, bar graph, and line graph.

Question 14.
What is speedometre?
Answer:
Speedometer is an instrument used for measuring on a vehicles dashboard, which indicates the speed of the vehicle when it is done. It requires the speed directly in km/h.

Question 15.
What is odometer?
Answer:
Odometer is an instrument for measuring the distance travelled by the vehicle. It records the distance travelled by the vehicle in kilometre.

Question 16.
Where will you find speedometers and odometers.
Answer:
Speedometers and odometers will be seen on the dashboards of buses, cars, and other vehicles.

Question 17.
Name some devices which are used to measure time.
Answer:
Quartz clock, sundial and sand clock are devices used to measure time.

Motion and Time Extra Questions

Question 1.
Complete the data of the table given below with the help of the distance-time graph given in figure.

Distance (m)	0	4	?	12	?	20
Time (s)	0	2	4	?	8	10

Answer:

Distance (m)	0	4	8	12	16	20
Time (s)	0	2	4	6	8	10

Question 2.
What do you understand by periodic motion? Give any examples.
Answer:
The motion which repeats itself after regular intervals of time, is called periodic motion. Periodic motion of a simple pendulum has been used to make clocks and watches.
Examples:

• The motion of the swing, to and fro motion of a simple pendulum.
• The rotation of the earth on its axis, and the revolution of the earth around the sun.

Question 3.
What are quartz clocks?
Answer:
The clocks or watches have an electric circuit with one or more cells are called quartz clocks. The time measured by quartz clocks is much more accurate than that by the clocks available earlier.

Question 4.
What do you mean by the statement; “car is moving with the speed of 70Km per hour”?
Answer:
Car is moving with the speed of 70 km per hour it means it will cover a distance of 70 km in one hour.

Question 5.
A spaceship travels 36000 km in one hour. Express its speed in km/s.
Answer:
Given, Distance travelled by spaceship = 36000 km
Time taken = 1 hour
We know, 1 hour =60 min= 60 × 60 = 3600 seconds
\(\text { Speed }=\frac{\text { Distance, } \text { travelled }}{\text { Time taken }}=\frac{36000}{3600}=10 \mathrm{~km} / \mathrm{s}\)

Question 6.
Plot a distance-time graph of the tip of the second hand of a clock by selecting 4 points on X-axis and Y-axis, respectively. The circumference of the circle traced by the second hand is 64 cm.
Answer:
Given the distance covered in 60 seconds = 64 cm
The distance covered in 15 seconds = 16 cm
Similarly, the distance covered in 30 seconds = 32 cm (30/60 x 64)
The distance covered in 45 seconds = 32 cm (45/60 x 64)
The circumference of circle traced by a second hand in 60 sec is 64 cm.

Time (s)	X	15	30	45	60
Distance (m)	Y	16	32	48	64

Here equal distance is covered in equal interval of time. So the graph will be a straight line.

Question 7.
A boy runs 20km in 2 hours. How long will he take to run 40 km at double the previous speed?
Answer:
A boy runs 20 km in 2 hours.
\(\text { Speed }=\frac{\text { Distance travelled }}{\text { Time taken }}=\frac{20}{2}=10 \mathrm{~km} / \mathrm{h}\)
He will take time to run 40 km at double the previous speed is (40/10)=4hours

Question 8.
Why do we need to measure time?
Answer:
We need to measure the time for the different reasons:

• Doctors need to measure the number of times the heartbeat in one minute for a patient.
• Farmers need to measure the time between sowing and harvesting of crops.
• A sportsman needs to measure the time he might take to complete an event.
• A traveller need to measure the time of his journey.
• Students need to measure the time to complete an event.

Question 9.
What are the difference between slow and fast motion?
Answer:
The differences between slow and fast objects.

S.No.	Slow motion	Fast motion
1)	An object which takes a long time to cover a certain distance is known as slow motion.	An object which takes shorter time to cover the certain distance is known as fast motion.
2)	Example : Motion of tortoise and snail.	Example : Racing car and leopard.

Question 10.
What are the factors on which the time period of a pendulum depends?
Answer:
The time period of a simple pendulum does not depend on the mass of the bob and nature of the material of the bob. It depends upon the length of the pendulum and acceleration due to gravity.

Question 11.
The average age of children of class VII is 12 years and 3 months. Express this age in
second.
Answer:
Given, the average age of children 12 years and 3 months
1 year = 365 days = 365 x 24 h [ 1 day = 24 h]
= 365 x 24 x 3600 s [1 h = 3600 s]
12 years = 31536000 s x 12 = 378432000 s
3 months = 30 x 3days = 30 x 3 x 24h
= 30 x 3 x 24 x 3600s
= 7776000s
So, total age in second = 378432000 + 7776000 = 386208000s.

Question 12.
Find the speed of a car that travels in 500 km in 5 hours.
Answer:
Given,Distance covered = 500 km
Time taken =5 hours
\(\text { Speed }=\frac{\text { Distance travelled }}{\text { Time taken }}=\frac{500}{2}=100 \mathrm{~km} / \mathrm{h}\)
Speed = 100 km/h

Question 13.
What are the points that should be considered while choosing the most suitable scale for drawing
Answer:
The following points should be considered while choosing the most suitable scale for drawing a graph:

• The difference between the highest and lowest values of each quantity.
• To utilise the maximum part of the graph paper.
• The intermediate values of each quantity, so that the scale chosen it is convenient to mark the values on it.

Question 14.
What does the path of an object look like when it is a non-uniform motion?
Answer:
In non-uniform motion, the path of an object can be a curved line, zigzag line or even a circle. It can have any shape. This is because in non-uniform motion speed is not constant. The direction of motion may change.

Question 15.
Convert 36km/h into m/s.
Answer:
To convert 36 km/h into m/s; Multiply by \(\frac{5}{18}\)
1km =1000m and 1 hour =3600s
\(\frac{1 \mathrm{~km}}{1 \text { hour }}=\frac{1000}{3600}=\frac{5}{18} \mathrm{~km} / \mathrm{h}=36 \times \frac{5}{18} \mathrm{~m} / \mathrm{s}\)

Extra Questions of Motion and Time Class 7

Question 1.
Write the differences between uniform motion and non-uniform motion.
Answer:
The difference between uniform motion and non-uniform motion are as follows:

S.No.	Uniform motion	Non uniform motion
1)	An object moving along a straight . line with a constant speed is said to be in uniform motion.	An object moving along a straight line with a constant speed, in the motion is said to be uniform motion.
2)	It covers equal distances at an equal interval of time.	It covers unequal distances at equal interval of time.
3)	The distance time graph is a straight line curved line.	The distance time graph shows a
4)	Average speed is similar to the actual speed of the object.	Average speed is different frome actual speed of the object.
5)	Rectilinear motion has zero acceleration.	Motion has non- zero acceleration.

Question 2.
Prem goes to the football ground to play football.
The distance-time graph of his journey from his home to the ground is given as figure.
i) What does the graph between points B and C indicate about the motion of Boojho?
ii) Is the motion between 0 to 4 min uniform or non uniform?
iii) What is his speed between 8 and 12 minutes of his journey?
Answer:
i) Prem’s speed is zero hence he will be in rest because the graph between B and C is parallel to time-axis.

ii) The graph is not straight line, so it is a non-uniform motion.
\(\text { Speed }=\frac{\text { Distance travelled }}{\text { Time taken }}=\frac{225-150}{12-8}=\frac{75}{4}=18.75 \mathrm{~m} / \mathrm{min}\)

Question 3.
How did ancestors measure a day, month and year?
Answer:
Our ancestors noticed that many events in nature repeat themselves after regular definite intervals of time. By looking at the regular events they were able to predict the day, month, and year.

• The time between one sunrise and the next was called a day.
• A month was measured from one new moon to the next.
• A year was measured as the time taken by the earth to complete one revolution.

Question 4.
What are the advantages of graphs ?
Answer:
The advantages of graphs are:

• It helps in the comparison of data in a better way.
• The interdependence of two variables can be established easily.
• The mean value of ratio of two variables can be accurately obtained without rigorous mathematical calculations.
• The probable value of variables can be calculated with the help of a graph within, or beyond the observed values from the mean value without any lengthy numerical computations.
• Another important advantage of the graph is that some of the salient features of the given experimental data can be seen visually, which cannot be easily concluded by simply looking the experimental data.

Question 5.
How will you make a line graph ?
Answer:
The following steps will be followed to make a graph:

• Draw two perpendicular lines to represent the two-axis and mark them as OX and OY.
• Show time along X -axis and distance along the Y -axis.
• Choose a scale to represent distance and another scale to represent the time on the graph.
• Mark values for the time and distance on the respective scales.
• Join all the points on the graph.

Question 6.
What information is provided by the distance-time graph?
Answer:
The information provided by the distance-time graph is as follows:

• It tells about the distance moved by the object only at some definite time intervals.
• We can find the distance moved by the object at any instant in time.
• We can calculate the speed of the object from the distance-time graph.

Case Based / Data – Based Questions

Hema was driving a car on the road, she said that the wheels of the car are moving along a straight line. But her friend, Ram who was riding a bicycle, said that the wheels of the car are moving circular. Then they decided rather than fighting themselves, it is better to ask their science teacher.

i) What is rotational motion?
Answer: The motion possessed by a body when it spins about a fixed axis, is called rotational motion.

ii) Name some types of motion.
Answer: The types of motion are circular motion, oscillatory motion, periodic motion, rectilinear motion etc.

iii) Among Hema and Ram who is correct? Explain.
Answer: Hema and Ram, both are correct because the wheels of the car is showing both types of motion i.e., rectilinear motion along the road as well as rotational or circular motion along fixed axis.

iv) What is rectilinear motion?
Answer: When the motion of a body along a straight line, it is known as rectilinear motion

These AP 7th Class Science Important Questions and 8th Lesson Reproduction in Plants Class 7 Extra Questions will help students prepare well for the exams.

Class 7 Science Reproduction in Plants Extra Questions

Reproduction in Plants Class 7 Important Questions

Question 1.
What is meant by reproduction?
Answer:
The process of producing a new organism from the existing organism (or the parent) of the same species is called reproduction.

Question 2.
What is pollination?
Answer:
Pollination is a process in which pollen grains get transferred from anther to the stigma of the flower.

Question 3.
Which type of pollination does the given figure indicate ?
Answer:
The type of pollination is self-pollination. If the ‘pollen’ is transported from the ‘anther’ of any flower to the ‘stigma’ of same flower, it is termed as ‘Self-Pollination’.

Question 4.
Pick the odd one out from the following on the basis of mode of reproduction and give reason for it. Sugarcane, Potato, Rice, Rose.
Answer:
The odd one out is rice. Sugarcane, potato and rose reproduce through vegetative propagation. Whereas rice reproduces by sexual reproduction.

Question 5.
What do you mean by vegetative propagation?
Answer:
Vegetative propagation is the ability of plants to reproduce by using vegetative parts like root, stem and leaves.

Question 6.
Why reproduction is essential for life process?
Answer:
Reproduction is essential for continuation of the species from generation to generation.

Question 7.
What is Zygote?
Answer:
Zygote is a diploid cell formed from the fusion of male and female gametes.

Question 8.
Define pollination.
Answer:
The transfer of pollen grains from the anther of a stamen to the stigma of a pistil is called pollination.

Question 9.
Name the various methods of asexual reproduction.
Answer:
Various methods of asexual reproduction are vegetative propagation, budding, fragmentation, spore formation.

Question 10.
What are pollen grains?
Answer:
Pollen grains are tiny spherical partules that contain the male gamete of a plant.

Question 11.
What is seed dispersal?
Answer:
The distribution or transfer of seeds from the place of their origin to a faraway place is known as seed dispersal.

Question 12.
What do you mean by fertilisation?
Answer:
The process in which the male gamete fuses with the female gamete to form a new cell (called zygote) is called fertilisation.

Question 13.
What is stamen?
Answer:
Stamen is a male reproductive organ of a plant. These are the little stalks with swollen top and lies inside the ring of petals. The stamen is made up of two parts, i.e., filament and another. The stalk of stamen is called filament and the swollen top of stamen is called anther.

Question 14.
Name any two hard fruits and any two fruits which are fleshy and juicy.
Answer:
Some fruits are hard like almonds and walnuts. Some fruits are fleshy and juicy such as mango and orange.

Question 15.
Define fragmentation.
Answer:
The process of asexual reproduction in which an organism breaks up into two or more fragments is called fragmentation. These fragments grow into new individuals.

Reproduction in Plants Extra Questions

Question 1.
In the figure given below, label the parts marked (a), (b) and (c)
Answer:

The parts in the given figure can be labelled as follows: When a pollen grain falls on the stigma of a flower it grows into a pollen tube downwards through the style towards the egg in ovary. A male gamete moves down the pollen tube and fuses with female gamete in ovary to form a zygote.

Question 2.
Coconut is a large and heavy fruit. How is it adapted for dispersal by water?
Answer:
Coconut contains an outer fibrous layer which enables them to float in water.This means it can drift in water bodies to dissimilar locations for a long time period. This way coconut is adapted for dispersal by water.

Question 3.
What are bisexual and unisexual flowers?
Answer:

• Unisexual flower: The flower which contains only one reproductive organ (i.e., either male or female) are called unisexual flowers. These are also called as an incomplete flower, E.g: papaya, watermelon, corn, cucumber, etc.
• Bisexual flower: The flower that contains both reproductive parts (i.e., male and female) in a single flower are called a bisexual flower. These are also termed as hermaphrodites or complete flower, E.g: rose, mustard, hibiscus, etc.

Question 4.
How does seed dispersal benefit to plants?
Answer:

• Seed dispersal avoids overcrowding of young plants around their parent plants.
• It helps in preventing competition between the plants and its own seedlings for sunlight, water and minerals.
• One of the benefits of seed dispersal is that it enables the plant to grow into new habitats for wider distribution and provides them with a better chance of survival.

Question 5.
Explain the types of reproduction in plants.
Answer:
There are two types of reproduction in plants. They are:

• Asexual reproduction : In this mode of reproduction, new plants are produced without seeds by involvement of single parent. New plants grow by means of vegetative propagation, budding, fragmentation, or spore formation.
• Sexual reproduction : In this mode of reproduction, new plants are produced through the formation of seeds. Male and female gametes fuse to form a zygote which later on develops into a seed. For example: Mango.

Question 6.
Write any three advantages of the vegetative propagation method.
Answer:
Following are the advantages of vegetative propagation:

• It is a fast method of reproduction.
• Plants produced by vegetative propagation have same features as that of parent plant.
• Seedless plants can be easily propagated.

Question 7.
How do fungi, spirogyra, and yeast reproduce?
Answer:

• Yeast reproduce by budding.
• Spirogyra that are present in waterbodies reproduce by fragmentation.
• Fungi reproduces asexually by spore formation.

Question 8.
How does an alga reproduce?
Answer:
Algae reproduce by a method known as fragmentation. The breaking down of filaments into fragments that grow into young ones is called fragmentation.

Question 9.
What are fruits? What are fleshy and dry fruits?
Answer:
Fruits are the ripened ovary of a flower. There are two types of fruits:

• Fleshy fruits : The fruits are fleshy and juicy like oranges, mango, apple etc.,are called fleshy fruits.
• Dry fruits: The fruits which are dry and hard like almonds and walnuts are called dry fruits.

Question 10.
How do plants such as mosses and ferns reproduce?
Answer:
Plants such as mosses and ferms are reproduced by means of spores. Spores are asexual reproductive bodies. Each spore is covered by a hard protective coat to withstand unfavourable conditions such as high temperature and low humidity. Hence, spores can survive for a long time. Under favourable conditions a spore germinates and develops into a new individual.

Question 11.
What are the differences between fertilisation and pollination ?
Answer:

S.No.	Pollination	Fertilisation
1)	The transfer of pollen grains from the anther of a stamen to the stigma of a pistil is called pollination.	Fertilisation is the fusion of male and female gametes of plants after a process of successful pollination.
2)	It occurs only in flowering plants.	It occurs in almost every plant in living organisms.
3)	It takes place on the outer part of the flower i.e., external mechanism.	It takes place inside the flower i.e., internal mechanism.
4)	There is no formation of pollen tubes in the process of pollination.	The pollen received from male anther and there is a transfer to the ovary by the pollen tube.
5)	It takes place before the process of fertilisation.	It takes place after the process of pollination.

Question 12.
Which part of a plant develops into the seed?
Answer:
The ovules within the ovary develop into the seeds of the plant. Each ovule that has transformed into a seed contains an embryo within it, which is protected by the walls of the ovule which develops into a hard shell.

Question 13.
How does fertilization occur in flower ? Where and how are seeds formed in plants?
Answer:
In asexual reproduction plants can give rise to new plants without seeds, whereas in sexual reproduction, new plants are obtained from seeds.

Extra Questions of Reproduction in Plants Class 7

Question 1.
Group the seeds given in figure (i) to (iii) according to their means of dispersion,
a) Seed dispersed by wind
b) Seed dispersed by water
c) Seed dispersed by animal

Answer:
The seeds and their means of dispersal are :
a) Seed dispersed by wind: Seeds of maple

• (winged seed which are light in weight) and seed of aak or madar
• (hairy outgrowth, which makes it lighter) can be dispersed by wind.

b) Seed dispersed by water : Seeds having spongy form and floating ability which are dispersed by water to different places.

c) Seed dispersed by animals : Seed of Xanthium (iii) are spiny with on them which gets attached to the bodies of animals and are carried to distant places. None of the seed given in the figure is dispersed by water.

Question 2.
Explain the structure of a flower.
Answer:
Flowers are the reproductive parts of the plants. A typical flower consists of the following parts.
a) Sepals : These are the green leaf-like outermost circle of the flower. They help in the preparation of the food.

b) Petals : Petals are the colourful and most attractive part of the flower. These lie inside the sepals.These are scented and attract insects for pollination.

c) Stamen : It is a male reproductive organ of a flower. There are two parts of stamen

• anther and
• filament. Anther contains pollen grains which have male gametes.

d) Pistil: It is the female reproductive part of the flowers. There are three main parts of the pistil. They are stigma, style and ovary. The ovary contains one or more ovules.The female gametes or the eggs are formed in an ovule.

Question 3.
Explain different types of pollination found in flowering plants.
Answer:
Pollination : The transfer of pollen grains from the anther of a stamen to the stigma of a pistil is called pollination.
Pollination takes place in two different ways :

• Self-pollination : The transfer of pollen grains from the anther of a flower to the stigma of the same flower or another flower of the same plant is known as self-pollination or autogamy.
• Cross pollination: The. transfer of pollen grains of a flower to the stigma of another flower of a different plant of the same species is called cross pollination or allogamy.

Question 4.
What is vegetative propagation? Describe vegetative propagation through different parts of the plant.
Answer:
Vegetative propagation is the ability of plants to reproduce by using vegetative parts like root, stem and leaves.
a) Vegetative propagation by roots : In some plants like sweet potato, dahlia, etc., a new plant develops through their roots and bulbs.

b) Vegetative propagation by leaves: In some plants leaves are hurried into the moist soil, the cut edges or margins of leaves develop a new plants that resemble to the parent, e.g. Bryopbyllum or sprout leaf plant.

c) Vegetative propagation by stems : In certain plants like potato, ginger, sugarcane etc, new plants grow from the stems of these plants. In potatoes these are small ‘eyes’ on the swollen stem. These eyes germinate to give rise to new plants. Ginger and turmeric also give rise to new plants from the small buds growing on their swollen stems.

Question 5.
Explain sexual reproduction in plants.
Answer:
Sexual reproduction occurs in plants having well developed reproductive parts in them. Flowers are the reproductive parts of the plant. Flowers can be unisexual i.e. having only male or female reproductive parts, and bisexual i.e., having both male and female reproductive parts.

Female reproductive part of the flower i.e. the pistil form female ovules and male reproductive parts i.e., Androecium give rise to male gametes. When male and female gametes fuse in the ovary of the flower the process of fertilisation takes place. Male gametes are carried to the female flowers far away by agents like wind, water, insects and animals. This is called pollination. After fertilisation, the ovary of the flower becomes pulpy and juicy to form fruits. The ovules become the seeds.

Question 6.
In the figure of a flower given under, label the parts whose below and give their names.

a) The part which contains pollen grains.
b) The part where the female gamete is formed.
c) The female reproductive part, where pollen grains germinate.
d) The colourful part of flower which attracts insects.
Answer:
The various parts of a flower whose functions are mentioned above are labelled as follows:

a) The part which contains pollen grains Anther.
b) The part where the female gamete formed is Ovary.
c) The female reproductive part where pollen grains germinate is Stigma.
d) The colourful part of flower which attracts insects is Petals.

Case Based / Data – Based Questions

Stamens are the male reproductive part and pistil is the female reproductive part. Flowers which contain either only pistil or only stamens are called unisexual flowers. Flowers which contain both stamens and pistil are called bisexual flowers. Corn, papaya and cucumber produce unisexual flowers, whereas mustard, rose and petunia have bisexual flowers.

Both male and female unisexual flowers may be present in the same plant or in different plants. Anther contains pollen grains which produce male gametes. A pistil consists of stigma, style and ovary. Ovary contains one or more ovules. The female gamete or the egg is formed in an ovule. In sexual reproduction a male and a female gamete fuse to form a zygote.

a) What are the male and female reproductive part of a flowers?
Answer: Stamen and pistil are the male and female reproductive part of a flower.

b) What are bisexual flowers?
Answer: Flowers which contain both stamens and pistil are çalled bisexual flowers.

c) Give any two examples of unisexual flowers?
Answer: Papaya, watermelon, corn, cucumber, etc., are examples of unisexual flowers.

d) How many ovules does an ovary contains?
Answer: Ovary contains one or more ovules.

These AP 7th Class Science Important Questions and 7th Lesson Transportation in Animals and Plants Class 7 Extra Questions will help students prepare well for the exams.

Class 7 Science Transportation in Animals and Plants Extra Questions

Transportation in Animals and Plants Class 7 Important Questions

Question 1.
Name the organ which is located in the chest cavity with its lower tip slightly tilted towards the left.
Answer:
The heart is the organ located in the chest cavity with its lower tip slightly tilted towards the left. It is roughly the size of a fist and beats continuously to act as pump for the transport of blood.

Question 2.
What is pulse?
Answer:
The throbbing sensation that occurs in arteries due to flowing of blood is called pulse.

Question 3.
What is heart beat?
Answer:
The rhythmic contraction and relaxation of heart muscles that produce a specific sound of lubb-dubb is called heartbeat.

Question 4.
What does the xylem transport?
Answer:
The function of the xylem is to transport water and nutrients from the roots to all parts of the plant.

Question 5.
Define blood.
Answer:
Blood is a fluid tissue that flows in blood vessels. It is red in colour and it flows through a network of tubes in whole body called blood vessels. It helps to carry nutrients and oxygen and removing waste materials.

Question 6.
What is platelet?
Answer:
Blood platelets are small, irregular, disc shaped particles formed in the bone marrow. These are colourless and help in the clotting of blood in a cut or wound.

Question 7.
What is meant by excretion?
Answer:
The process of removal of waste materials produced in the cells of the living organism is called excretion.

Question 8.
What is urine?
Answer:
The mixture of various wastes with water filtered from the blood is called urine.

Question 9.
What is the purpose of using stethoscope by doctors?
Answer:
A stethoscope reads heartbeats as diaphragm amplies the rounds of heartbeat when placed on specific areas.

Question 10.
Who discovered the circulation of blood?
Answer:
The English physician, William Harvey discovered the circulation of blood.

Question 11.
What is pulse rate?
Answer:
The number of beats per minute is called the pulse rate.

Question 12.
What is vascular tissue?
Answer:
Plants have pipie-like vessels to transport water and nutrients from the soil are called vascular tissues.

Question 13.
What do you mean by Xylem and Phloem?
Answer:
Xylem : The vascular tissue for the transport of water and nutrients in the plant is called the xylem.
Phloem : The food has to be transported to all parts of the plant by the vascular tissue called the phloem.

Question 14.
Define red blood cells.
Answer:
Red blood cells are disc shaped, biconcave cell in the blood that contains haemoglobin, lacks a nucleus and transports oxygen and carbon dioxide to and from the tissues.

Question 15.
What are ventricles?
Answer:
The two lower chambers of heart are called ventricles.

Transportation in Animals and Plants Extra Questions

Question 1.
Paheli uprooted a rose plant from the soil. Most of the root tips, with root hairs got left behind in the soil. She planted it in a pot with new soil and watered it regularly. Will the plant grow or die? Give reason for your answer.
Answer:
Possible changes may take place:

• Without the root hairs, the roots will not be able to absorb water and nutrients and the plant will die.
• The stem of the rose plant may grow into new plants, hence plant survives.
• The rose plant may not be able to survive in a different type of soil.

Question 2.
a) Name the only artery that carries carbon dioxide rich blood. ‘
b) Why is it called an artery if it does not carry oxygen-rich blood?
Answer:
a) The pulmonary artery carries blood from left ventricle to the lungs carries carbon-dioxide rich blood.
b) The pulmonary artery does not carry oxygen rich blood but it carries blood away from the heart like all other arteries. Therefore, it is called an artery.

Question 3.
What is circulatory system?
Answer:
Circulatory system or blood circulatory system is the main transport system in human beings and animals.The transport system carries materials like carbon dioxide, oxygen and nutrients to the different parts of the body with the help of circulating fluid i.e. blood.

Question 4.
What do you mean by dialysis ? Explain.
Answer:
Dialysis is the artificial process used for getting rid of waste and unwanted water from the blood by the machines. Dialysis machines contain a tank with solution of water, glucose and salt. The blood of the patient is allowed to pass through the solution and for the removal of the wastes. The cleaned blood is pumped back to a vein.The dialysis continues till entire blood has been purified.

Question 5.
Differentiate between arteries and veins.
Answer:
Differences between arteries and veins are as follows :

S.No.	Arteries	Veins
1)	They carries pure blood from heart to different organs of the body.	They collect the impure blood from different parts of the body.
2)	They carry oxygenated blood, except pulmonary artery.	They carry oxygenated blood, except pulmonary vein.
3)	They are thick walled and deeply seated.	They are thin walled and superficially located beneath the skin
4)	They have no valves.	They have also to prevent back flow of blood.

Question 6.
Why do sponges and hydra lack blood ?
Answer:
Animals such as sponges and Hydra do not posses any circulatory system. The water in which they live brings food and oxygen as it enters their bodies. The water carries away waste materials and carbon dioxide as it moves out. Thus, these animals do not need a circulatory fluid like the blood.

Question 7.
Write the differences between RBCs and WBCs.
Answer:
Differences between RCBs and WBCs are as follows :

S.No.	RBCs	WBCs
1)	They have biconcave disc shaped.	They have irregular shape.
2)	They are red in colour.	They are colourless.
3)	They are rich in haemoglobin.	They are lack of haemoglobin.
4)	They are non-motile.	They are motile.
5)	They do not have a nucleus at maturity.	They have a large characteristic nucleus.
6)	Their life span is 120 days.	They have a short life span of 5 to 20 days.

Question 8.
What are the three main types of blood vessels and write their functions?
Answer:
The three main types of blood vessels are:

• Arteries : These are the blood vessels which carry oxygenated pure blood from heart to all other parts of the body.
• Veins : These are the blood vessels which collects the deoxygenated impure blood from the whole body and send it to the heart.
• Capillaries: These are the network of thin tube like structures which connect the arteries and veins together.

Question 9.
Name the process and the organ which help in removing the following wastes from the body.
a) Carbon dioxide
b) Undigested food
c) Urine
d) Sweat
Answer:

S.No.	Root hairs	Xylem	Urethra
1)	Arteries	Kidneys	Veins
2)	Atria	Capillaries	Heart
3)	Ureter	Pholem	Urinary bladder

Question 10.
What are the functions of blood ?
Answer:
The functions of blood are:

• It carries oxygen from the lungs to the cells of the body.
• It transports waste for removal from the body.
• It regulates the body temperature.
• It transports the digested food to all parts of the body from small intestine.

Question 11.
What is transpiration? How it is useful to the plants?
Answer:
Transpiration is the loss of process of evaporation of excess through stomata in plants. This process helps plants to supply water from roots to top parts of plants thereby distributing water to all parts of the plant. It also helps in keeping the plants cool.

Question 12.
What is transportation ? Where does it takes place?
Answer:
Transportation is the process of transport of soluble products of photosynthesis from the leaves to other parts. It occurs in phloem.

Question 13.
What is sweat ? Write any two functions of sweat.
Answer:
Sweat is the liquid waste of the body that is produced by the sweat glands present in our skin. Sweat contains water, some unwanted salts and urea in a very small amount.The two major functions of sweat are as follows :

• It helps to remove excess water, salt and urea from the body.
• It helps to keep our body cool during hot summer days.

Extra Questions of Transportation in Animals and Plants Changes Class 7

Question 1.
Read the following terms given below.

Group the terms on the basis of the categories given below.
a) Circulatory system of animals.
b) Excretory system in human.
c) Transport of substances in plants.
Answer:
The terms on the basis of the categories mentioned above can be grouped as follows:
a) Circulatory system : Arteries, atria, capillaries, veins, and heart together form the circulatory system.In the circulatory system, the heart (consists of two atria and two ventricles) acts as a pump to put out blood. The blood vessels (arteries, veins and capillaries) act as tubes through which blood flows in the whole body.

b) Excretory system: Urethra, kidneys, ureter and urinary bladder form the excretory system in human.The excretory system of human consists of two bean-shaped kidneys that filter blood to form urine. Urine goes into, the urinary bladder through tubes called ureters. It goes out from body through the opening at the end of a tube called urethra.

c) Transport of substances in plants: Root hairs, xylem and phloem are transport of . substances in plants.Transport system in plants consists of xylem and phloem. The water absorbed by root hairs from soil reaches xylem to move upward to stem, branches and leaves. Phloem carries food from leaves to other parts.

Question 2.
Describe the process of absorption and transportation of water and minerals in plants?
Answer:
The plant root have root hairs which absorb water and minerals in the form of solution from soil. This process is called absorption. This water and minerals are then transported to other parts of plant i.e., stem, leaves and flowers through a special tissue called xylem. Then food is synthesised within leaves of plant and is transported in all parts of plant including roots, through phloem. There produces are called transportation.

Question 3.
Describe the structure of the human heart.
Answer:
a) Heart is a triangle shaped organ. It is made up of a cardiac muscles. It is located in the chest cavity slightly towards the left side.

b) It lies between the two lungs and above the diaphragm.The size of our heart is roughly equal to our left closed and is enclosed in a protective cover called pericardium fist. The heart is hollow inside.

c) It pumps blood to all parts of the body. It beats 72 to 80 times per minute throughout the life.

d) The heart has four compartments called as chambers. The upper two chambers of heart are called atria (singular, atrium) and the lower two chambers of heart are called ventricles.

e) On the left side of heart are left atrium and left ventricle and on the right side of the heart are right atrium and right ventricle.

f) The heart is separated by a partition called septum (from right side of the heart to the left side) to avoid mixing of pure and the impure blood. The chambers contain valves which ensure the flow of blood in one direction only.

g) The right auricle receives carbon dioxide rich blood from various parts of the body. The right ventricle pumps, the blood to the lungs. Inside lungs, carbon dioxide is exchanged with oxygen.

h) The left article receives oxygen rich blood from the lungs. The left ventricle pumps, this a blood to the rest of the body.

Question 4.
Explain the excretion in birds, lizards, fishes, and dogs and humans.
Answer:
The way of elimination of waste products from the body of animals depends upon the availability of the water.The animals like lizards, birds, snakes, etc., have less water availability. These animals excrete a white colour, semi solid product waste material in the form of uric acid pellets. Aquatic animals like fishes excrete ammonia as their waste product. This ammonia is excreted in the gaseous form which directly gets dissolved in water. Dogs and human beings excrete urea.

Question 5.
Explain human circulatory system with the help of a diagram.
Answer:
Circulating system is the life support system of our body that provide our body cells with nutrients and oxygen. It takes away waste products from the body. Since our circulatory system consist of heart, blood, blood vessels and lungs.

• Blood is the fluid that carry oxygen and nutrients to various parts of the body and it takes away waste and carbon dioxide from the cells for elimination.
• Blood vessels comprises of arteries, veins, and capillaries. Arteries carry oxygen-rich blood from the heart to all parts of the body.
• Veins are the vessels that carry carbon dioxide rich blood from all parts of the body back to the heart.
• Capillaries are single walled vessels which exchange of gases and nutrients from the cells.
• Heart is a muscular organ with four chambers which pumps blood throughout the body. It pumps carbon dioxide rich blood to the lungs for purification.
• When it receives oxygen rich blood from the lungs it again pump this blood to arteries transportation to various body parts.
• Lungs help in the exchange of gases between air we breathe in and the blood. It helps in the elimination of carbon dioxide from blood and making it rich in oxygen content.

Question 6.
Explain the excretory system in human beings.
Answer:
When our body uses food, water and air, it produces some by-products or unwanted substances. These are called waste materials. The waste materials are present in the blood has to be removed from the body. A system to filter the waste is required. This is done by the blood capillaries in the kidney. When the blood reaches the two kidneys, it contains both useful and harmful substances.

The useful substances are absorbed back into the blood after filtration in kidneys. The waste dissolved in water is removed as urine. From the kidneys, the urine goes into the urinary bladder through tubes called ureters. It is stored in the bladder and is passed out through the muscular tube called the urethra. The kidneys, ureters, urinary bladder, and urethra form the excretory system in humans.

Case Based / Data – Based Questions

While learning bicycle, Mohan lost his balance and fell down. He got a cut on his knee and it started bleeding. Her brother Ramu, on seeking this asked him to put pressure on the area with a clean handkerchief. He immediately rushed to his home to call his parents.

a) How does applying pressure to a bleeding would help?
Answer: By applying a pressure to a bleeding would we restrict the blood vessels manually and prevents too much loss of blood from the wound.

b) When we get a small bruises, blood stops automatically after sometime. Why?
Answer: Bleeding stops automaticaliy in small bruises after sometime due to clotting of blood.

c) What would be the colour of wounded area? Why?
Answer: The colour of the wounded area will be dark red due to the formation of clot.

d) Which type of blood cells are responsible for clotting of blood?
Answer: Blood platelets are responsible for clotting of blood.

These AP 7th Class Science Important Questions and 6th Lesson Respiration in Organisms Class 7 Extra Questions will help students prepare well for the exams.

Class 7 Science Respiration in Organisms Extra Questions

Respiration in Organisms Class 7 Important Questions

Question 1.
Where does cellular respiration takes place?
Answer:
Cellular respiration takes place in cells of all organisms.

Question 2.
Name the two modes of respiration.
Answer:
The two modes of respiration are:

• Aerobic respiration
• Anaerobic respiration

Question 3.
What is respiration?
Answer:
Respiration is a biological process in which food is utilised to produce energy.

Question 4.
What is breathing?
Answer:
Breathing is the process in which air rich in oxygen is taken inside and air rich in CO₂ is given out, with the help of respiratory organs.

Question 5.
Define the terms:
a) Inhalation
b) Exhalation
Answer:
a) Inhalation : Taking in of air rich in oxygen into the body is called inhalation.
b) Exhalation : Giving out air rich in carbon dioxide from the body to the external environment is called exhalation.

Question 6.
Our nostrils has hair and mucous. What is the need to have them in our nasal cavity?
Answer:
Our nostrils possess hair and mucous lining. These helps to filter the air that goes into the lungs. They stop the germs and dust from entering into our body.

Question 7.
Which group of organisms possess spiracles?
Answer:
Spiracles are plesent only in insects.

Question 8.
What do you mean by breathing rate?
Answer:
The number of times a person breathes in a minute is termed as breathing rate. An adult human being can inhale and exhale 15-18 times in a minute.

Question 9.
Which gas present in the air is essential for aerobic respiration? What is the role of oxygen during respiration?
Answer:
Oxygen present in air is essential for aerobic respiration and it help to break down food and release energy during respiration.

Question 10.
When do our muscle cells respire anaerobically?
Answer:
When there is a temporary deficiency of oxygen in the muscle cells, they begin to respire anaerobically.

Question 11.
What do you mean by diaphragm?
Answer:
A muscular partition separating the abdominal and thoracic activities is called diaphragm.

Question 12.
Why smoking should be avoided?
Answer:
Smoking damages lungs. Smoking is also linked to cancer. It must be avoided.

Question 13.
What are anaerobes?
Answer:
There are some organisms such as yeast that can survive in the absence of air. They are called anaerobes.

Question 14.
Name the parts of respiratory system of human?
Answer:
The respiratory system consists of the nose, pharynx, larynx, trachea, bronchi, diaphragm and lungs.

Question 15.
Where are the lungs of human beings are present?
Answer:
The lungs of the human beings are present in the chest cavity.

Respiration in Organisms Extra Questions

Question 1.
What are spiracles?
Answer:
Spiracles are small openings present on the sides of the body of insects, like cockroaches. The spiracles on the body of insects are connected to a network of thin air tubes called tracheae which spreads into the whole body of the insect, where the exchange of gases takes place.

Question 2.
Pick the odd one out from each of the groups given below on the basis of respiratory organs. Give reason for your answer.
a) Cockroach, grasshopper, snail, ant
b) Lizard, cow, earthworm, snake
c) Crocodile, whale, dolphin, fish
d) Snake, tadpole, crow, goat
Answer:
a) Snail is the odd one, as it does not breathe by means of tracheae.
b) Earthworm is the odd one, because it breathes through its skin and it does not have lungs.
c) Fish is the odd one, as most fish breathe through their gills and do not have lungs.
d) Tadpole is the odd one, as it breathes through gills and do not have lungs.

Question 3.
Insects and leaves of a plant have pores through which they exchange gases with the atmosphere. Can you write two points of differences between these pores with respect to their position, number and extension into the body?
Answer:
Spiracles in insects and stomata on the leaves of a plant are pores through which gaseous exchange takes place. The differences between spiracles and stomata on the basis of their position, number and extension into the body are as follows:

• Spiracles are present on the sides of insects body while stomata are present on the lower surface of leaves in the plants.
• Spiracles are lesser in number as compared to stomata.
• Spiracles are part of an extensive network of tracheal system which is absent in the leaves.

Question 4.
What is the Aerobic respiration?
Answer:
The process of respiration which takes place in the presence of oxygen is called aerobic respiration. During aerobic respiration, glucose is completely broken down into carbon dioxide and water and energy is released. Aerobic respiration takes place in mitochondria.
It can be shown by the following equation :

Aerobic respiration is seen in most of the organisms such as humans (man), dogs, cats, lions, elephants, cows, buffaloes, goats, snakes, earthworms, frogs, fishes, etc.

Question 5.
What do you mean by anaerobic respiration?
Answer:
The respiration which takes place in the absence of oxygen is called anaerobic respiration. In this procesș glucose is not completely broken down into carbon dioxide and water. An intermediate compound is formed with the release of less amount of energy during this process. It can be shown as follows:

Question 6.
What are yeasts? Write its uses.
Answer:
Yeast is a single-celled organism. During anaerobic respiration (also called fermentation), yeast produces ethanol or alcohol as a by product which is used in making wine and beer. The carbon dioxide produced by yeast is used in the bread making industry. The CO₂ gas released during this process causes the bread dough to rise.

Question 7.
What causes muscle cramps? How can you relieve the pain from muscle cramps?
Answer:
The muscle cramps occur when cells respire anaerobically. The partial breakdown of glucose produces lactic acid. The accumulation of lactic acid causes muscle cramps. The pain from muscle cramps can be reduced by following methods:

• Massaging the area
• Bathing with hot water
• Resting

Hot water bath or massage improves circulation of blood. As a result, the supply of oxygen to the muscle cells increases. The increase in the supply of oxygen results in the complete breakdown of lactic acid into carbon dioxide and water.

Question 8.
Define respiration in plants.
Answer:
Plants take in oxygen from the air and give out carbon dioxide through tiny pores called stomata, situated in the back of the leaves. Oxygen is used to break down glucose into carbon dioxide and water inside the cell.

Question 9.
Explain the respiration in Earthworm.
Answer:
Earthworms breathe through their skins. The skin of an earthworm feels moist and slimy on touching.Oxygen enters the body of the earthworm through diffusion and exits in a similar way.

Question 10.
Observe the given diagram of human respiratory system. List the organs from (A) to (G).
Answer:
The human respiratory system have following organs:

• A – Ribs
• B – Trachea
• C – Pharynx
• D – Diaphragm
• E – Lungs
• G – Oral cavity
• F – Nasal passage

Question 11.
What are the stages of respiration?
Answer:
Respiration takes place in the following stages:

• External respiration or gaseous exchange: The exchange of gases between the environment and the body is called external respiration or gaseous exchange. This is also called breathing.
• Internal respiration : It is a biochemical process involved in respiration which breaks down the food using inhaled oxygen to release energy and takes place in the tissues within the cells of an organism.Thus, this is called the cellular or tissue respiration.

Question 12.
Describe the various types of respiratory organs found in animals?
Answer:
In animals, there are definite respiratory organs for exchange of gases.

• In earthworm and leech exchange of gases takes place through moist, thin and vascular skin.
• In insects the trachea are the respiratory organs.
• In fishes the gills are the respiratory organs.
• Higher animals like mammal and birds including man have lungs for respiration.

Question 13.
Explain the process of breathing.
Answer:
The air inhaled is transported to every part of the body and ultimately is transported to every cell in the body. The oxygen in the air helps in the breakdown of food in the cells to release energy. This process is called cellular respiration.

Question 14.
Define cellular respiration.
Answer:
The air inhaled is transported to all parts of the body and ultimately to each cell in the body. In the cells, oxygen in the air helps in the breakdown of food. The process of breakdown of food in the cell with the release of energy is called cellular respiration. Cellular respiration takes place in the cells of all organisms.

Extra Questions of Respiration in Organisms Class 7

Question 1.
Paheli participated in a 400 m race competition held at her school and won the race. When she came home she had mixed feelings of joy and pain as she had cramps in her leg muscles. After a massage, she was relieved of the pain. Answer the following questions related to situation.
a) What can be the possible reasons for the pain in her legs?
b) Why did she fell comfortable after a massage?
Answer:
a) The pain in her legs could be because of the accumulation of lactic acid in the muscles. During heavy exercise or running etc., the muscle cells respire anaerobically and produce lactic acid.

b) The massage or hot water bath gives relief from muscle cramps or pain, because it improves the circulation of blood leading to increased supply of oxygen to the muscle cells. It helps in complete breakdown of lactic acid into carbon dioxide and water.

Question 2.
Decribe the respiratory system in humans.
Answer:
Respiratory system is responsible for the process of respiration. It involves exchange of gases, i.e., oxygen and carbon dioxide between body and surrounding. When we breathe in, the air enters through our nostrils. Hair and the most inner lining of the nose prevent the dust and germs from entering the respiratory system. The air passing the nasal passage gets warm and moist and enter the lungs through trachea and bronchi. In lungs, each bronchus divided into smaller tubes called bronchioles.

At the other end of these bronchioles, there are very small air sacs called alveoli. These air sacs are surrounded by blood vessels. These blood vessels absorb oxygen present in the air. we breathe in. Carbon dioxide present in the blood is released into the air sacs and is expelled out of our body when we breathe out. Thus during breathing, exchange of carbon dioxide and oxygen takes place in the lungs.

Question 3.
Differentiate between respiration and breathing.
Answer:
Differences between respiration and breathing are as follows :

S.No	Respiration	Breathing
1)	Respiration is a biological process in which food is utilised to produce energy.	Breathing is the process in which air rich in oxygen is taken inside & air rich in CO2 is given out, with the help of respiratory organs.
2)	It takes place inside the cells, respiratory organs.	It takes place at the surface of the
3)	The exchange of gases takes place between blood and the tissues of the body.	The exchange of gases takes place between the blood and the external environment.
4)	Respiration takes place in cells and cell organelles, including mitochondria, etc.	Breathing occurs through respiratory organs, including the nose, lungs, etc.
5)	In this process nutrients are oxidised to liberate energy.	The nutrients are not oxidised to liberate energy.               .

Question 4.
What is meant by breathing rate ? Explain the mechanism of inhalation and exhalation which are responsible for the breathing rate?
Answer:
The number of times a person breathes in a minute is termed as breathing rate. During breathing, inhalation and exhalation takes place alternatively. A breath means one inhalation plus exhalation. During inhalation two processes occur together, i.e., the muscles between the ribs contract causing the ribcage to move upward and outward, while the diaphragm contracts and moves downwards.

This upward and downward movement of ribcage and diaphragm respectively increases the space in the chest cavity and makes it larger. As the chest cavity becomes larger, it sucks air from outside the lungs and lungs get filled up with air and expand. During exhalation, ribs move down and inwards, while diaphragm moves up to its original position. This reduces the size of the chest cavity and air is pushed out of the lungs.

Question 5.
What are the differences between cellular respiration and breathing?
Answer:
The differences between cellular respiration and breathing are as follows :

S.No	Cellular respiration	Breathing
1)	The process of breakdown of food in the cell with the release of energy is called cellular respiration.	Breathing is the process in which air rich in oxygen is taken inside and air rich in CO2 is given out, with the help of respiratory organs.
2)	Energy is released in this process.	Energy is not released in this process.
3)	It is a biochemical process.	If physical process.
4)	The production of carbon dioxide gas takes place.	Carbon dioxide is given out and it. oxygen is taken in from the air.
5)	It is an intracellular process.	It is an extracellular process.

Question 6.
Observe the given figures carefully and answer the following questions.
a. The amount of CO₂ be the highest in which jar. Why ?
b. The amount of CO₂ be the lowest in which one and why?
Answer:
a. Jar C has highest amount of CO₂. lt is because the mice kept under the jar will breathe out CO₂ continuously increasing its amount in the jar. In other jars, the CO₂ present inside will be used up by the plants for photosynthesis. So, its amount will decrease.

b. The amount CO₂ will be the lowest in jar A. It is because in jar A, CO₂ released during respiration is used by the plant for the process of photosynthesis.

Case Based/Data – Based Questions

Mohan a stall owner was preparing dough for making Poori’s. He added a pinch of yeast and sugar to the dough and left it in a warm place. After few hours, the dough had risen. There was a sour smell too.

a) Why did the dough rise?
Answer:
The dough rose due to the release of carbon dioxide during anaerobic respiration by the yeast.

b) Why did the dough smell sour?
Answer:
Yeast, during anaerobic respiration also produces alcohol which results in the sour smell of dough.

c) Why was sugar added to the dough?
Answer:
Sugar is added into the dough, because it acts as a food for yeast, Yeast on incomplete breakdown of sugar or food produces CO₂, alcohol and energy (in less amount).

d) What would have happened if the dough was kept in the refrigerator, soon after it was prepared?
Answer:
If the dough was kept in the refrigerator soon after it was prepared, then dough will neither rise nor become sour. Yeast requires high temperature to grow, multiply and to respire. At low temperature, the yeast will not multiply or respire and therefore, no CO₂ or alcohol would be formed.

These AP 7th Class Science Important Questions and 5th Lesson Physical and Chemical Changes Class 7 Extra Questions will help students prepare well for the exams.

Class 7 Science Physical and Chemical Changes Extra Questions

Physical and Chemical Changes Class 7 Important Questions

Question 1.
Define a physical change.
Answer:
The change in which the identity of the substance does not change is called a physical change.

Question 2.
Melting of wax is a change where a solid changes to a liquid state. Give one more such change which you observe in your surroundings.
Answer:
Melting of ice is also a change where solid changes into liquid state.

Question 3.
What kind of change is shown by tearing of paper?
Answer:
Tearing of paper is a physical change although, it cannot be reversed.

Question 4.
What are the physical properties of a substance?
Answer:
Shape, size, colour and state of a substance are some of its physical properties of a substance.

Question 5.
What is the colour of copper sulphate solution obtained when iron nails are dipped in it?
Answer:
When iron nails are dipped in copper sulphate solution, then the colour of the solution changes to green.

Question 6.
Define galvanisation.
Answer:
This process of depositing a layer of zinc on iron is called galvanisation.

Question 7.
Name any two methods by which rusting of iron can be prevented.
Answer:
Rusting of iron can be prevented by oiling or painting and by galvanisation.

Question 8.
Which gas is released when baking soda is mixed with vinegar?
Answer:
Carbon dioxide is released when baking soda is mixed with vinegar.

Question 9.
Define rust.
Answer:
When an iron object is left exposed to moist air, it chemically reacts with oxygen and water in the air to form a red-brown flaky substance called rust.

Question 10.
Give any two examples of physical changes and chemical changes.
Answer:
Freezing of water, melting of wax, boiling of water, etc., are examples of physical change. Burning of wood or paper, souring of milk, digestion of food etc., are examples of chemical changes.

Question 11.
What kind of change is crystallisation?
Answer:
Crystallisation is a physical change because no new substance is formed.

Question 12.
What is the nature of aqueous solution of magnesium oxide?
Answer:
The aqueous solution of magnesium oxide is basic in nature, as it turns red litmus to blue.

Question 13.
What are the essential factors responsible for rusting?
Answer:
The essential factors responsible for rusting are :

• Presence of moisture and
• Presence of oxygen in air.

Question 14.
Complete the following reactions:
a) MgO+H₂O →
b) CO₂+Ca(OH)₂ →
Answer:
a) Magnesium oxide (MgO)+ Water H₂O) → Magnesium hydroxide [Mg(OH)₂]
b) Carbon dioxide (CO₂)+ Lime water [Ca(OH)₂] → Calcium Carbonate (CaCO₃) + Water (H₂O)

Question 15.
What is blue vitriol?
Answer:
Vitriol is the generic name for a group of chemical compounds made up of sulfates of various metals, originally iron or copper. Crystals of copper sulphate penta hydrate are blue in colour. Is a solution of copper sulphate in water is commonly known as blue vitriol.

Physical and Chemical Changes Extra Questions

Question 1.
What are the characteristics of a physical change?
Answer:
The characteristics of a physical change are:

• No new substance is formed in this change.
• It is a temporary change and is generally reversible.
• A temporary change in colour may take place.
• Very little energy (heat, etc.) is either absorbed or evolved.

Question 2.
Classify the following processes into physical or chemical changes.
a) Beating of aluminium metal to make aluminium foil
b) Digestion of food
c) Cutting of a log of wood into pieces
d) Burning of crackers
Answer:
Beating of aluminium metal to make aluminium foil and cutting of a log of wood into pieces are physical changes. Digestion of food and burning of crackers are chemical changes.

Question 3.
Write word equations for two chemical reactions with the help of materials given in the box.
Air, copper sulphate, iron, vinegar, iron oxide, carbon dioxide, iron sulphate, copper, lime water, water.
Answer:
The reaction are given below:

• Iron + Air + Water → Iron oxide
• Copper sulphate + Iron→ Iron sulphate + Copper

Question 4.
What are the characteristics of a chemical change?
Answer:
The characteristics of a chemical change are :

• A chemical change is irreversible in nature.
• It is a permanent change.
• A permanent change in colour might occur in a chemical change.
• A new substance is always formed in chemical change.
• The composition of a substance gets changed during a chemical change.
• A lot of energy in the form of a heat, light etc., is either absorbed or given out in a chemical change.

Question 5.
Magnesium ribbon burns in air and changes to white substance, i.e., magnesium oxide. When magnesium oxide dissolves in water, what type of change take place? Give reason in support of your answer. Express the change in the form of equation.
Answer:
Mixing of ash obtained by the burning of magnesium with water is a chemical change. When magnesium is burnt in air, it forms magnesium oxide in the form of white ash.
Magnesium (Mg)+ Oxygen (O₂) → Magnesium oxide (MgO)
When magnesium oxide dissolves in water, it forms a new substance, magnesium hydroxide.
Magnesium oxide (MgO)+Water (H₂O) → Magnesium hydroxide Mg(OH)₂
So, it is a chemical change.

Question 6.
Compare the energy changes involved during a physical and a chemical change.
Answer:
Yes, all types of changes involves energy changes. During a change, energy is either evolved or absorbed. In case of chemical change the absorption and evolution of energy will takes place. In case of physical change the absorption and evolution of energy does not takes place.

Question 7.
What is a chemical change?
Answer:
A change in which one or more new substances are formed is called a chemical change. A chemical change is also called a chemical reaction. Most of the chemical changes are irreversible. They involve in evolution of heat, light, gas or sound. For example burning of paper or wood, digestion of food etc.

Question 8.
Define crystallisation. Give an example.
Answer:
The process of obtaining crystals of pure substances from their solutions is called crystallisation. It is a method used to purify solids. It is a physical change. For example : Copper sulphate crystals can be obtained from the solution of pure copper sulphate. The solution is known as blue vitriol.

Question 9.
Explain the following:
a) Lime water turns milky on passing carbon dioxide gas through it.
b) Bubbles are produced when acetic acid is added to a solution of sodium hydrogen carbonate.
Answer:
a) When carbon dioxide (CO₂) reacts with the lime water [Ca(OH)₂], calcium carbonate (CaCO₃) and water (H₂O) is formed.
Ca(OH})₂+CO₂ → CaCO₃+H₂O

b) When baking soda (NaHCO₃) is added to acetic acid (CH₃COOH), then carbon dioxide (CO₂) gas is formed which causes appearance of bubbles. CH₃ COOH+NaHCO₃ → CO₂₊ other substance.

Question 10.
Explain why process of digestion is a chemical change.
Answer:
In the process of digestion, the various food materials break down to form new substances which can be absorbed by the body. So, the process of digestion is a chemical change.

Question 11.
Give an example of a chemical reaction for which of the following reactions?
a) A change in colour is observed
b) A gas is involved
c) Change in taste is observed
d) Sound is produced
e) Light is produced
f) Heat is produced
Answer:
a) Reaction between copper sulphate solution and iron metal.
b) Reaction between baking soda and vinegar (carbon dioxide is evolved).
c) Setting of curd from milk. Taste of milk changes to sour in curd.
d) Burning of crackers.
e) Burning of fuel produces light.
f) Reaction between hydrochloric acid and sodium hydroxide produces heat.

Question 12.
Is burning always a desirable change?Explain.
Answer:
No. it is not always a desirable change. It is desirable during cooking of food, burning of candle, burning of fossil fuels to drive engines and other machines. However, it is undesirable at other times as it causes a lot of damage, E.g: forest fire causes a lot of damage to plants, animals and our ecosystem. Therefore, it is not always a desirable change.

Extra Questions of Physical and Chemical Changes Class 7

Question 1.
State the differences between physical and chemical changes.
Answer:
The differences between physical and chemical changes are:

S.No.	Physical change	Chemical change
1)	It is generally a reversible process.	It is generally a irreversible process.
2)	No new substance is formed.	A new substance is formed.
3)	It is a temporary change.	It is a permanent change.
4)	Only physical state and physical properties of the substance are changed.	The physical as well as the chemical properties of the substance are changed.
5)	There is no energy change in these changes.	Energy is either absorbed or evolved in these changes.
6)	Example : Melting of ice.	Example : Burning of paper.

Question 2.
What is rusting ? Suggest and explain any three methods for prevention of rusting.
Answer:
Iron reacts with oxygen and moisture present in the atmosphere to form a brown, flaky substance called rust. Rust of iron is undesirable because the layer of rust formed falls off, exposing the metal to further rusting. As a result, iron object becomes weak with the passage of time.
Iron ( Fe ) + Oxygen (O₂ from the air) + Water (H₂O) → Rust (iron oxide Fe₂O₃)

• Methods to prevent rusting: Applying oil or grease on the surface inhibits the iron surface from, coming into touch with the atmosphere, which prevents rusting.
• Galvanisation: A layer of a more reactive metal, such as zinc, is deposited on the surface of iron to protect it from rust.
• Painting: Applying a layer of paint to the metal’s surface stops it from coming into contact with the atmosphere once more.
• Alloying: To make alloys, iron can be combined with other metals and non-metals. Rust resistance is a feature of alloys. Stainless steel is an important iron alloy.

Question 3.
Answer the following questions
a) How ozone layer acts as a protective shield ?
b) What is stainless steel? How is stainless steel made? State an important property of stainless steel.
Answer:
a) The ozone layer protects us from the harmful ultraviolet radiations which come from the sun. Ozone absorbs ultraviolet radiations coming from the sun and breaks down to form oxygen. In this way, ozone layer absorbs harmful ultraviolet radiations.
b) Stainless steel is an alloy of iron. When iron is mixed (or alloyed) with carbon, chromium and nickel, then stainless steel is obtained. Stainless steel does not rust at all.

Question 4.
Why temperature is important in our daily lives?
Answer:
Chemical changes are very important in our lives because all new substances are formed as a result of chemical changes. For example, if a metal is to be extracted, from an ore, such as iron from iron ore, we need to carry out a series of chemical changes. A medicine is the end product of a chain of chemical reactions. Useful new materials, such as plastics and detergents are produced by studying chemical changes.

Question 5.
What happens when vinegar is added to baking soda? What happens when this gas is passed through lime water?
a) Vinegar + Baking soda Carbon dioxide + Other solutions
b) Carbon dioxide (CO₂)+Lime water [Ca(OH)₂] → Calcium Carbonate (CaCO₃)+Water (H₂O)
Answer:
When baking soda and vinegar are mixed with each other, carbon dioxide gas is released. When carbon dioxide is passed through lime water, calcium carbonate is formed. Calcium carbonate to makes lime water appear milky. The turning of lime water into milky solution is a standard test of carbon dioxide. The following reactions takes place.

Question 6.
What happens when iron nails are dipped in copper sulphate solution?
Answer:
When iron is dipped in copper sulphate solution, a brown layer of copper gets deposited on the surface of the iron nails after some time. This happens due to the reaction between the copper sulphate and iron. Also, the colour of the copper sulphate changes from blue to green due to the formation of copper sulphate.
Iron nail + Copper sulphate solution (blue) → Iron sulphate solution (Green) + Copper (brown)

Question 7.
Give two examples for each of the following cases:
a) Physical changes which are reversible.
b) Physical changes which are not reversidele.
c) Chemical changes
Answer:
a) (i) Folding of paper
(ii) Melting of ice.

b) (i) Tearin of paper
(ii) Breaking of glass

c) (i) Reaction between vinegar and baking soda
(ii) Burning of a matchstick

Case Based / Data – Based questions

Sneha bought big iron table for their shop. Sneha leaves the table in the open for a few days, ‘it acquires a film of brownish substance, called rust.
a) Do you think rust is different from iron?
b) Can you change rust back into iron by some simple method?
c) Do you think formation of rust on iron is a chemical change?
d) Give two other examples of a similar type of change.
Answer:
a) Yes, rust is iron oxide (Fe₂O₃). Thus, rust and iron are not the same substance.

b) No, rusting of iron is a chemical change because in this reaction, a new substance, rust (iron oxide) is formed. It cannot be reversed by any simple method.

c) Yes, rusting of iron is a chemical change. During the rusting of iron, it combines with the oxygen in the presence of water (moisture) to form a new compound ‘iron oxide’. This iron oxide is a rust.
Iron + Oxygen + Water → Iron oxide (Rust)
It is a permanent change which cannot be reversed back.
So, rusting of iron is a chemical change.

d) Two other examples are:

• Setting of curd from milk.
• Burning of magnesium ribbon to form magnesium oxide.

These AP 7th Class Science Important Questions and 4th Lesson Acids Bases and Salts Class 7 Extra Questions will help students prepare well for the exams.

Class 7 Science Acids Bases and Salts Extra Questions

Acids Bases and Salts Class 7 Important Questions

Question 1.
What are acids?
Answer:
The chemical compounds which are sour in taste are called acids. Examples: Lemon juice, curd, vinegar etc.

Question 2.
What are bases ?
Answer:
The substances which are bitter in taste and feel soapy on touching are known as bases. Examples : Baking soda, lime water etc.

Question 3.
Look at the given reaction.
Hydrochloric acid + Sodium hydroxide (base) → Sodium chloride (salt) + Water Sodium chloride formed in this reaction remains in solution form. Can we get solid sodium chloride from this solution? Suggest a method (if any).
Answer:
Sodium chloride is soluble in water hence a solution of sodium chloride in water is formed. Sodium chloride can be separated from this solution by evaporation.

Question 4.
Define indicators along with examples.
Answer:
The special type of substances which are used to test whether a substance is acidic or basic by indicating a colour change are called indicators. Examples: Turmeric, litmus, China rose etc.

Question 5.
What are neutral substances?
Answer:
The substances which are neither acidic nor basic are called neutral substances.

Question 6.
What are natural indicators? Give any two names of the indicators that occur naturally.
Answer:
Indicators which are obtained from natural sources are called natural indicators. Litmus, turmeric, red cabbage, China rose, etc., are some common natural indicators used widely to show the acidic or basic character of substances.

Question 7.
Which acid is present in our stomach ?
Answer:
Hydrochloric acid in small amount is present in our stomach.lt helps us to digest food.

Question 8.
Name the acid present in the following:
a) Tamarind
b) Spinach
c) Lemons and oranges
Answer:
a) The acid present in the tamarind is tartaric acid.
b) The acid present in the spinach is oxalic acid.
c) The acid present in the lemons and oranges is citric acid.

Question 9.
How many types of litmus papers are there? What are they?
Answer:
There are two types of litmus papers. They are red and blue litmus paper.

Question 10.
Which is the most commonly used natural indicator?
Answer:
The most commonly used natural indicator is litmus.

Question 11.
What makes the soil acidic ?
Answer:
Excessive use of chemical fertilisers makes the soil acidic.

Question 12.
What kills fish and other organism present in the water bodies?
Answer:
Releasing of factory waste containing acids or bases.

Question 13.
Define neutralisation.
Answer:
Neutralisation can be defined as the reaction between an acid and a base.

Question 14.
What are salts ?
Answer:
The product formed other than water by the neutralisation reaction of an acid and a base is called salt. Salt may be acidic, basic or neutral in nature. Example: Sodium chloride.

Question 15.
What colour does the phenolpbthalein give when the solution is basic?
Answer:
Phenolphthalein turns pink in bases.

Acids Bases and Salts Extra Questions

Question 1.
Define organic acids.
Answer:
Organic acids are the acids found naturally in plants and animals, For example: Vinegar contains acetic acid, lemon juice contains citric etc., are organic acids.

Question 2.
Look at figure which shows solutions taken in test tubes A, B, C and D. What colour is expected when a piece of red iitinus paper is dropped in each test tube? Nature of the solutions is given in the table for your help.

Test tube	Nature of solution	Change in colour of red litmus
A	Neutral
B	Basic
C	Acidic
D	Neutral

Answer:

Test tubesolution in water	Nature of solution	Change in colour of red litmus
A (Milk)	Neutral	No change
B (Baking powder)	Basic	Colour will change to blue
C (Vinegar)	Acidic	No change
D (Glucose)	Neutral	No change

Question 3.
While playing in a park, a child was stung by a wasp. Some elders suggested applying paste of baking soda and others lemon juice as remedy. Which remedy do you think is appropriate and why ?
Answer:
Wasp sting injects a liquid into the skin which is acidic in nature. Hence baking soda is applied as it is basic in nature and neutralises the acid.

Question 4.
How the factory wastes neutralised ?
Answer:
The wastes of many factories contain acids. If they are allowed to flow into the water bodies, these acids will kill fish and other organisms.Therefore the factory wastes are neutralised by adding basic substances.

Question 5.
Why do you mean by soil treatment ?
Answer:
Most of the plants grow best in neutral soil, excessive use of chemical fertilisers makes the soil acidic. Plants do not grow well when the soil is either too acidic or too basic. When the soil is too acidic, it is treated with bases like quick lime (calcium oxide) or slaked lime (calcium hydroxide). If the soil is basic, organic matter (compost) is added to it. Organic matter releases acids which neutralises the basic nature of the soil.This process of maintaining soil pH balance is called soil treatment.

Question 6.
What is litmus ? Write its use ?
Answer:
Litmus is the most commonly used indicator which is extracted from lichens.lt is naturally purple in colour but with acids, it turns red and with bases, it turns blue. It is used to detect whether the given substance is an acid or a base.

Question 7.
A small amount of hydrochloric acid is always produced in the stomach. Is it useful or harmful for us ? If excess of acid is produced in the stomach, what should we do?
Answer:
A small amount of hydrochloric acid produced in the stomach is useful as it helps to digest our food and it can kill the harmful bacteria that may enter into the stomach along with the food. If excess of acid is produced in the stomach causes indigestion.We should take an antacid such as milk of magnesia which contains magnesium hydroxide to neutralise the excess acid.

Question 8.
Explain the use of China rose as an indicator.
Answer:
China Rose is a good example of a natural indicator. It has an orange colour in neutral conditions. It changes colour from dark pink to magenta when exposed to acid. It becomes green in basic conditions.

Question 9.
Name any three acids used in the laboratory.
Answer:
Acids which are mostly used in laboratory as below :

• Hydrochloric acid (HCl)
• Sulphuric acid (H₂SO₄)
• Nitric acid (HNO₃)

Question 10.
What are the properties of acids ?
Answer:
The properties of acids are :

• Acids are sour in taste.
• Acids turns blue litmus into red.
• Acids have pH less than 7.
• Acid reacts with meted to form hydrogen gas.
• Acids do not react with ammonium salts.
• Acids are generally found in citrus fruits like lemon, vinegar, curd, amla etc.

Question 11.
What are the properties of bases ?
Answer:
The properties of bases are :

• Bases are bitter in taste and soapy to touch,
• Base turns red litmus to blue.
• It give pink colour with phenolphthalein indicator.
• Bases are generally found in lime water, soap, window cleaner, Milk of Magnesia.
• Bases react with ammonium salts to give ammonium gas.

Question 12.
What does an ant inject when it bites ? How will you treat it ?
Answer:
When an ant bites, it injects the acidic liquid (formic acid) into the skin. The effect of the acid can be neutralised by rubbing moist baking soda (sodium hydrogen carbonate) or calamine solution, which contains zinc carbonate.

Question 13.
How will you prepare lime water ?
Answer:
To prepare limewater, take some water in a tumbler and add some lime (chuna) into it. Stir the solution and keep it for some time. Pour a little from the top. This is lime water.

Question 14.
Explain the use of phenolphthalein as an indicator.
Answer:
Phenolphthalein is a man-made marker. It is colourless in neutral circumstances. When exposed to basic circumstances, it turns pink, and when exposed to acidic ones, it turns colourless.

Extra Questions of Acids Bases and Salts Class 7

Question 1.
What is acid rain ? List some of the damaging effects of acid rain.
Answer:
The rain containing excess of acids called an acid rain. The rain becomes acidic because carbon dioxide, sulphur dioxide and nitrogen dioxide dissolve in rain drops to form carbonic acid, sulphuric acid and nitric acid respectively.

Effects of acid rain are:

• Acid rain makes the water of lakes, ponds and rivers too acidic due to which fish and other aquatic animals get killed.
• Acid rain eats up the leaves of the trees gradually. By losing leaves, the trees die. Acid rain also damages crop plants in the fields.
• Acid rain damages the metal structures like steel bridges, etc., when it falls on them.
• Acid rain damages the surfaces of buildings and monuments made up of marble.

Question 2.
Explain any three neutralisation reactions in our daily life.
Answer:

• Ant bite : When an ant bites, it injects the acidic liquid (formic acid) into the skin. The effect of the acid can be neutralised by rubbing moist baking soda (sodium hydrogen carbonate) or calamine solution, which contains zinc carbonate.
• Indigestion : Our stomach contains hydrochloric acid. It helps us to digest food but too much of acid in the stomach causes indigestion. Sometimes, indigestion is painful. To relieve indigestion, we take an antacid such as milk of magnesia which contains magnesium hydroxide. It neutralises the effect of excessive acid.
• Factory wastes: The wastes of many factories contain acids. If they are allowed to flow into the water bodies, the acids will kill fish and other organisms. The factory wastes are, therefore, neutralised by adding basic substances.

Question 3.
Common indicators cannot determine how much acidic or basic solution has. Explain.
Answer:
Common indicators such as litmus, methyl orange and phenolphthale in can easily tell us whether a solution is acidic or alkaline but they cannot easily tell how much a given solution is stronger than another acidic solution. It means they cannot tells us that degree of acidic or basic nature of a solution.

Question 4.
A farmer was unhappy because of his low crop yield. He discussed the problem with an agricultural scientist and realised that the soil of his field was either too acidic or too basic. What remedy would you suggest the farmer to neutralise the soil?
Answer:
The reason for low crop yield in farmer’s field was that the soil at a place is either too acidic or too basic. The soil may be acidic or basic naturally. The excessive use of fertilisers in the fields also makes the soil too acidic. When the soil is too acidic, it is treated with base such as quicklime (calcium oxide) or slaked lime (calcium hydroxide) which neutralises the excess acid present in the soil and reduces its acidic nature. If the soil is too basic, then decaying organic matter (called manure or compost) is added it. The decaying organic matter releases acid which neutralises the excess bases present in the soil and reduces its basic nature.

Case Based / Data – Based Mentions

Sneha and her family went for a trip around river Yamuna, in Delhi is polluting it deliberately. They saw that factory wastes and municipal waste are dumped into it untreated. They thought of spreading an awareness programme. They even wrote to Municipal corporation of the state, suggesting them ways to reduce this kind of pollution.

i) How factory or domestic wastes affect the quality of river?
Answer: Factory or domestic wastes changes colour, acidity or basicity, microbial growth, temperature, turbidity etc., of the water.

ii) How the process of neutralisation is affecting changing some of the quality of water?
Answer: If the river water is it too acidic or basic, club. So by neutralising the pollutants before discharging into the river can at least change water quality to neutral.

iii) Suggest any two ways to reduce the pollution of the river Yamuna?
Answer: Pollution of the river can be reduced largely by making the people aware that how they can contribute in their own level to control water pollution and giving strict guidelines to industries situated near river bank to treat their waste suitably before discharging it into the river.

iv) How the factory wastes are neutralised?
Answer: The factory wastes are neutralised by adding basic substances.

These AP 7th Class Science Important Questions and 3rd Lesson Heat Class 7 Extra Questions will help students prepare well for the exams.

Class 7 Science Heat Extra Questions

Heat Class 7 Important Questions

Question 1.
Define clinical thermometer?
Answer:
The thermometer that measures our body temperature is called a clinical thermometer.

Question 2.
What is the use of kink in clinical thermometer?
Answer:
It prevents mercury level from falling on its own when thermometer is removed from the body.

Question 3.
Shopkeepers selling ice blocks usually cover them with jute sacks. Explain why.
Answer:
A jute sack is a thermal insulating material and it helps ice not to melt immediately. So, shopkeepers must use insulating materials like sack, saw dust, newspaper etc., to cover the ice.

Question 4.
What is temperature?
Answer:
A reliable measure of the hotness of an object is called its temperature.Temperature is measured by a device called thermometer.

Question 5.
What are the ranges of a clinical thermometer and a laboratory thermometer?
Answer:
The range of a clinical thermometer is generally from 35°C to 42°C
The range of a laboratory thermometer is generally from -10°C to 110°C

Question 6.
What is a laboratory thermometer?
Answer:
A laboratory thermometer is used for measuring the temperature of substances in a laboratory.

Question 7.
Do all hot bodies radiate heat?
Answer:
Yes, all hot bodies radiate heat.

Question 8.
What are the various methods of transfer of heat?
Answer:
The various methods of transfer of heat are :

• Conduction
• Convection
• Radiation

Question 9.
In a mercury thermometer, the level of mercury rises when its bulb comes in contact with a hot object. What is the reason for this rise in the level of mercury?
Answer:
As the temperature increases, expansion of mercury takes place in the capillary tube which leads to the rise in the level of mercury in thermometer.

Question 10.
Define sea breeze.
Answer:
The flow of cool air from the sea towards the land to replace the hot air on land is called sea breeze. This phenomenon takes place during the day.

Question 11.
Which type of clothes should be preferred in the month of June in India?
Answer:
Light coloured clothes should be preferred in the month of June in India.

Question 12.
Why dark-coloured clothes are preferred in winter?
Answer:
Dark-coloured clothes are preferred in winter because they absorb most of the heat falling on them and keep us warm.

Question 13.
Name the units of temperature.
Answer:
Temperature is measured in units of degrees Celsius (°C) or degrees Fahrenheit (°F).

Question 14.
Why do we wear woollen clothes during winter?
Answer:
Wool is a poor conductor of heat. Moreover, air is trapped in between the wool fibres which acts as insulator. This air prevents the flow of heat from our body to the cold surroundings. So, woollen clothes keeps us warm during winter.

Question 15.
How does the transfer of heat to take place in water or air?
Answer:
The transfer of heat to take place in water or air by the process of convection.

Heat Extra Questions

Question 1.
A circular metal loop is heated at point O as shown in figure.
a) In which direction, would heat flow in the loop ?
b) In which order, the pins at points P,Q and R fixed with the help of wax fall if points O, P, Q and R are equidistant from each other?
Answer:

a) The heat will flow in the direction from O to P and O to R .
b) At first the pins at R and P will fall simultaneously. followed by the pin at Q.

Question 2.
It is advised not to hold the thermometer by its bulb while reading it. Explain, why.
Answer:
It is advised not to hold the thermometer by its bulb while reading it because if we hold a thermometer by its bulb, the level of mercury in the bulb increases from the actual reading due to our body temperature.

Question 3.
What is convection?
Answer:
The mode of transfer of heat from the hotter part of a fluid (liquid or gas) to its colder parts by the movement of the liquid (or gas) itself is known as convection. The transfer of heat by convection can take place only in liquids and gases. It is due to the reason that the particles in liquids and gases can move about freely.

The transfer of heat by convection cannot take place in solids because the particles in the solids are fixed at a place and cannot move about freely. It is also not occurred in empty space or vacuum because there are no particles of any kind in empty space which can move and transfer heat.

Question 4.
Define conduction.
Answer:
The mode of transfer of heat from hotter part of a material to its colder part or from a hot material to a cold material in contact with it, without the movement of material as a whole, is known as conduction. In all the solids, heat is transferred by the process of conduction.

Question 5.
What is radiation ?
Answer:
Radiation is the transfer of heat between objects that are not in direct touch. The two items may be solids or liquids, but they are not in contact. Heat is transferred from a distance when a heated object radiates heat into the environment. There is no need for a medium for radiation. Because it emits heat to the surroundings, a hot object cools down on its own.

Question 6.
While constructing a house in a coastal area, in which direction should the windows preferably face and why?
Answer:
The windows of coastal areas should preferably face in the direction of sea.The sea breeze coming from sea keeps the house cool during the day time.

Question 7.
What is the use of a maximum-minimum thermometer?
Answer:
A maximum-minimum thermometer is used by the weathermen to give weather reports stating the highest and lowest temperature recorded for a particular day.

Question 8.
What are the conductors and insulators of heat ?
Answer:

• Conductors: The materials which allow heat to pass through them easily are conductors of heat.
  Example : aluminium, iron and copper.
• Insulators : The materials which do not allow heat to pass through them easily are insulators of heat.
  Example : plastic and wood.

Question 9.
What are the effects of heat ?
Answer:
The effects of heat are :

• When an object is heated, then it becomes hotter and may get expand. So, in this heat may change the state of the body like ice can also get change into the water.
• Heat sometimes acts as a catalyst to speed up the chemical reaction.
• Heat can even kill the bacteria as well.

Question 10.
Why is mercury preferred in thermometers in place of water?
Answer:
Mercury used due to the following reasons:

• It has greater visibility than water.
• It expands uniformly.
• It does not stick to the walls.
• It remains liquid at room temperature.
• It is shiny and easy to see.

Question 11.
At a camp site there are tents of two shades. One made with black fabric and the other with white fabric. Which one will you prefer for resting on a hot summer afternoon? Give reason for your choice. Would you like to prefer the same tent during winter?
Answer:
We will prefer white fabric tent in case of summer as white is a bad absorber and a good reflector of heat. But in case of winter, we should not use white fabric tent, we should use black fabric tent as it absorbs all colours of light from the sun and keeps us warm inside the tent.

Question 12.
Explain the maximum – minimum thermometer and digital thermometer.
Answer:
Maximum – minimum thermometer : It is the thermometer used by the weathermen to give weather reports stating the highest and lowest temperature recorded for a particular day.
Digital thermometer: Mercury is a toxic substance (poisonous substance) and hence it is very difficult to dispose of safely if a thermometer breaks. These days, digital thermometers are available which do not use mercury.

Question 13.
Differentiate between two modes of transfer of heat, i.e. convection and conduction.
Answer:
Difference between convection and conduction are as follows :

Conduction	Convection
1) The mode of transfer of heat from the hotter part material to its colder part or from a hot material to a cold material in contact with it without the movement of material as a whole. So, this phenomenon is known as conduction.	1) The mode of transfer of heat from the hotter part of a fluid to its colder parts by the movement of liquid itself. So, this phenomenon is known as convection.
2) In all the solids, heat is transferred by, the process of conduction.	2) In all the liquids and gases, heat is transferred by the process of convection.

Extra Questions of Heat Class 7

Question 1.
What are the precautions to be taken while reading a clinical thermometer?
Answer:
Following precautions to be taken while reading a clinical thermometer:

• Thermometer should be washed before and after each use, preferably with an antiseptic solution.
• Ensure that before use the mercury level is, below 35C
• Do not wash the thermometer with hot water.
• Do not hold the thermometer by the bulb while taking the readings because in such cases, the temperature of our hand will also effect the reading.
• Read the thermometer keeping the level of mercury along the line of sight.
• Handle the thermometer with care, as you handle any glass articles.

Question 2.
Explain the structure of a clinical thermometer and state its special features with the help of a diagram.
Answer:
A clinical thermometer consists of a long, narrow, uniform glass tube having a thin and uniform bore.There is a glass bulb at one end of the glass tube which consists of mercury.The kink is present above the bulb. On the glass tube, we can see a temperature scale, usually a celsius scale.
Features:

• There is a very short range of temperature of a clinical thermometer, i.e., from 35°C to 42°C.
• A clinical thermometer has a kink in its glass tube which is to prevent the back flow of mercury into the thermometer bulb when the thermometer bulb is removed from the mouth of a patient. This kink prevents the mercury level in the thermometer tube from falling on its own.

Question 3.
Write the differences between heat and temperature.
Answer:
The differences between heat and temperature are as follows :

S.No	Heat	Temperature
1)	It is form of energy in a body of intensity of heat.	The temperature of a body is the parameter.
2)	The main feature of heat it is that it travels from the hotter region to	The temperature increases when heated and temperature falls when cooled.
3)	Its SI unit is Joule (J)	Its SI unit is Kelvin (K)
4)	Calorimeter is used to measure the heat in a body.	Temperature can be measured by  the thermometers.
5)	It is denoted by Q.	It is denoted by T.

Question 4.
How does the heat travel in the air? Explain the sea breeze and land breeze with the help of diagram.
Answer:
Heat travels in the air by convection. The blowing of sea breeze and land breeze in coastal areas is generally occurred due to the convection of heat in air.

Sea breeze: In coastal areas during the day time, the breeze generally flows from the sea towards the land is called sea breeze. The land gets heated faster than water during the day. Due to this, the air over the land becomes hotter and lighter and rises up.Cool air from water rushes in towards land to fill the space. Hence, the windows in coastal areas are made to face the sea to receive the cool sea breezes.

Land breeze: The breeze blowing from the land towards the sea is called land breeze. During the night, the land loses heat faster than water and becomes cooler and the air over the sea is now warmer due to which, it rises up and the cooler air over the land rushes to take its place. Therefore, we observe a land breeze at night.

Question 5.
What are the different modes of heat transfer ? Explain.
Answer:
Flow of heat from one object to another, whether solid or liquid is called a transfer of heat. Heat always flows from a body at a higher temperature to another body at lower temperature. There are three modes of transfer of heat:

Convection: The mode of transfer of heat from the hotter part of a fluid (liquid or gas) to its colder parts by the movement of the liquid (or gas) itself is known as convection. The transfer of heat by convection can take place only in liquids and gases.

Conduction : The mode of transfer of heat from hotter part of a material to its colder part or from a hot material to a cold material in contact with it, without the movement of material as a whole, is known as conduction. In all the solids, heat is transferred by the process of conduction.

Radiation : It is the transfer of heat between objects that are not in direct touch. The two items may be solids or liquids, but they are not in contact. Heat is transferred from a distance when a heated object radiates heat into the environment. There is no need for a medium for radiation. Because it emits heat to the surroundings, a hot object cools down on its own.

Question 6.
State the precautions to be observed while using a laboratory thermometer.
Answer:
Precautions to be,observed while using a laboratory thermometer.

• Handle the thermometer with care. If it hits against some hard object, it can break.
• Thermometer should be kept upright not tilted.
• The bulb of the thermometer should be surrounded from all sides by the substance of which the temperature is to be measured.
• The bulb should not touch the surface of the container.
• Do not move the thermometer while measuring the temperature of the substance.
• Never hold the thermometer by the bulb while reading it.
• Read the temperature of the object when the thermometer is in the substance.

Case Based / Data – Based Questions

Srikanth likes to have curd in his lunch. He even knows for that for setting curd, a small amount of curd is added to warm milk. The microbes present in the curd helps in setting the curd, if the temperature of the mixture remains approximately between 35°C to 45°C. But he is worried because it is winter and the room temperature remains a much below the range which makes setting of curd a difficult.

i) Suggest a way to Srikanth to set curd in such a situation.
Answer:
Srikanth can set curd by keeping the container near the gas stove while cooking or keeping the container wrapped in a woollen material or inside a heat resistant container.

ii) Why setting of curd during winter season become difficult?
Answer:
In winter season, temperature is very low. Low temperature inhibits the activity and the growth of microbes present in the curd and thus making of curd difficult.

iii) What is the temperature of the mixture ?
Answer:
The temperature of the mixture remains approximately between 35°C to 45°C.

These AP 7th Class Science Important Questions and 2nd Lesson Nutrition in Animals Class 7 Extra Questions will help students prepare well for the exams.

Class 7 Science Nutrition in Animals Extra Questions

Nutrition in Animals Class 7 Important Questions

Question 1.
How can you say that humans are heterotrophs?
Answer:

• Humans get food from plants or animals which in turn eat plants.
• Thus, we can say that humans are directly or indirectly depends on plants for food.

Question 2.
Why does tooth decay occur?
Answer:
When food remains stuck in teeth, bacteria feed on them. As a result, lactic acid produced, which causes the destruction of enamel. This leads to tooth decay. Chocolates, sweets, soft drinks and other sugar products are the major culprits of tooth decay.

Question 3.
What are villi? What are their functions?
Answer:

• Inner wall of small intestines have thousands of finger – like out growths called villi.
• They absorb the digestive food for assimilation.

Question 4.
What are the components in the buccal cavity ? How does the diet change there ?
Answer:

• Buccal cavity contains tongue, teeth and secretions of salivary glands.
• Carbohydrates digestion starts here.

Question 5.
How does we get good health?
Answer:

• Healthy body leads to healthy mind.
• When all our body system functions properly, we say that we are in good health.
• So, one should avoid bad habits and maintain healthy life-style.

Question 6.
How do you appreciate the saprotrophs as they clean the environment ?
Answer:

• Saprotrophs grow on the dead bodies, decompose them and mix them with soil.
• Thus that help us by cleaning the earth surface by removing the dead and decaying matter.
• Hence, I appreciate the saprotrophs.

Question 7.
How do you appreciate the role of teeth in digestive system ?
Answer:

• Holozoic organisms (animals) take food from the outside in the form of solid or liquid.
• The teeth in the mouth break the food into small pieces and grind the pieces into paste for easy digestion.
• The teeth help of animals to tear the hardest meat also. So, I appreciate the role of teeth in digestive system.

Question 8.
How do you protect your health ?
Answer:

• Inever attempt the bad habits like smoking, chewing of tobacco, drinking of alcohol.
• I will minimize the eating of sweets, fatty foods, junk foods and drinking of soft drinks.
• I will follow and practice good habits like asanas, exercises and games.
• I will maintain good hygienic habits like brushing of teeth, bathing, drinking of water etc. regularly.

Question 9.
Draw a neat and labelled diagram of amoeba ?
Answer:

Question 10
Write a short note on nutrition in Niarfish?
Answer:
Amazing tact: Starfish feeds on animals covered by hard shells of calcium carbonate. After opening the shell, the starfish pops Out its stomach through its mouth’to eat the soft animal Inside the shell. The stomach then goes back into the body and the food is slowly digested.

Question 11.
What are the different compartments of alimentary canal through which the food passes through?
Answer:

• Buccal cavity
• Food pipe or oesophagus
• Stomach
• Small intestine
• Large intestine ending in the rectum and
• Anus

Question 12.
What happens to the food inside the body?
Answer:

• The food components gradually get digested as food travels through the various compartments.
• The inner walls of the stomach and small intestine and the various glands associated with the canal such as salivary glands, the liver and the pancreas secrete digestive juices.
• These digestive juices convert complex substances of food into simpler ones.

Question 13.
What is ingestion? Where does it occur?
Answer:

• The process of taking food into the body is called ingestion.
• It occurs in mouth.

Question 14.
Where do find salivary glands? What do they secrete?
Answer:

• The mouth has the salivary glands.
• The secrete Saliva.
• It contains an enzyme called salivary anylase.

Question 15.
Draw a neat and labelled diagram showing the movement of the food in the oesophages of the alimentory canal?
Answer:

Question 16.
Draw the diagram of tongue showing different regions having different taste buds?
Answer:

Question 17.
Describe the structure of stomach?
Answer:

• The stomach is a thick walled bag.
• It’s shape is like a flattened.
• It is the widest part of the alimentary canal.
• It receives food from the food pipe at one end and opens into the small intestine at the other.

Question 18.
What are the different secretions of the stomach?
Answer:
1. The inner lining of the stomach secretes

• Mucous
• Hydrochloric acid and
• digestive.

2. The mucous protects the lining of the stomach.
3. Hydrochloric acid many bacteria that enter along with the food and makes the medium in the stomach acidic and helps the digestive juices to act.

Question 19.
Where does the protein digestion start in the alimentary canal ?
Answer:

• Protein digestion starts in stomach.
• The digestive juices breakdown the proteins into simpler substances.

Question 20.
Write a short note on small intestine ?
Answer:

• The small intestine is highly coiled and is about 7.5 metres long.
• It receives secretions from the liver and the pancreas.
• Intestinal wall also secretes juices.

Question 21.
What is liver and what is it’s importance in digestion?
Answer:

• The liver is a reddish brown gland situated in the upper part of the abdomen on the right side.
• It is the largest gland of our body.
• Liver secretes ‘bile juice’ which plays an important role in the digestion of fats.

Question 22.
What is gall bladder? What is it’s function?
Answer:

• Gall bladder is a sac like structure present near the liver.
• It stores bile juice which is secreted from liver.

Question 23.
What are the end products of different food components ?
Answer:

• Carbohydrates – Glucose
• Fats – Fatty acids and glycerol
• Proteins – Amino acids.

Question 24.
What are Villi? What is their function in small intestine?
Answer:

• The inner walls of small intestine have thousands of finger like projections. These, are called Villi.
• The villi increase the area of absorption of the digested food.

Question 25.
Write a short note on large intestine?
Answer:

• The large intestine is wider and shorted than small intestine.
• It is about 1.5 metre in length.
• It’s function is to absorb water and some salts from the undigested food material.

Question 26.
What is called egestion?
Answer:
The faecal matter is removed through the anus from time to time. This is called egestion.

Question 27.
Why do ruminants digest cellulose?
Answer:

• The grass is rich in cellulose, a type of carbohydrate.
• In ruminants like cattle, deer, etc., bacteria present in rumen helps in digestion of cellulose.

Nutrition in Animals Extra Questions

Question 1.
What change does the food undergo inside the mouth ?
Answer:

• We chew the food with the teeth and break it down mechanically into small pieces.
• Carbohydrates are digested in the mouth.
• Food also mixed with saliva and thrown into the stomach.

Question 2.
How does holozoic nutrition take place in amoeba ?
Answer:
Amoeba is a microscopic single-celled organism found in pond water. Amoeba has a cell membrane, a rounded, dense nucleus and many small bubble-like vacuoles in its cytoplasm. Amoeba constantly changes its shape and position. It pushes out one, or more finger-like profections, called pseudopodia or false feet for movement and capture food. Food vacuole forms around the captured food. Food get digested in it, observed into the cytoplasm and assimilates. Finally undigested food is sent out by opening this vacuole out at the body surface.

Question 3.
What happens to the food in the stomach ?
Answer:

• Stomach is a muscular sac like structure.
• Food is grinded well and mix with its juices.
  Proteins digestion starts in the stomach.
• Hydrochloric acid in the stomach kills bacteria in the food.

Question 4.
How does drinking of alcohol and consuming tobacco products damage our health?
(OR) What are the risks of consuming alcohol and smoking/ chewing tobacco ?
Answer:

• Bad habits like smoking/chewing of tobacco and drinking of alcohol effect our health adversely.
• Drinking of alcohol can lead to liver diseases, digestive problems. It causes cancer of the mouth, throat, oesophagus and liver.
• When consuming tobacco products, tobacco particles stick to teeth gums and skin of the mouth cavity which leads to swelling, injury, pain and also causes throat and intestine cancer.

Question 5.
What are the uses of different types of teeth?
Answer:
There are four types of teeth. They are:

• Incisors: These are used to biting and cutting of food like apple, bread etc.
• Canines: These are used to tear the food like meat, sugarcane etc.
• Premolars: These are used to chew and grind the food.
• Molars: These are also used to chew and grind the food further more fine.

Question 6.
How do you protect your health ?
Answer:

• I never attempt the bad habits like smoking, chewing of tobacco, drinking of alcohol.
• I will minimize the eating of sweets, fatty foods, junk foods and drinking of soft drinks.
• I will follow and practice good habits like asanas, exercises and games.
• I will maintain good hygienic habits like brushing of teeth, bathing, drinking of water etc. regularly.

Question 7.
How do you appreciate the role of teeth in digestive system ?
Answer:

• Holozoic organisms (animals) take food from the outside in the form of solid or liquid.
• The teeth in the mouth break the food into small pieces and grind the pieces into paste for easy digestion.
• The teeth help of animals to tear the hardest meat also.
  So, I appreciate the role of teeth in digestive system.

Question 8.
Draw a neat diagram showing the arrangement of teeth and different types of teeth?
Answer:

Question 9.
Write a short note on Pancreas ?
Answer:

• The pancreas is a large cream coloured gland located just below the stomach.
  The pancreatic juice acts on carbohydrates, fats and proteins and changes them into simpler form.
• It also acts as endocrine gland.

Question 10.
Write the process of assimilation in our body?
Answer:

• The surface of the villi absorbs the digested food materials.
• The absorbed substances are transported via the blood vessels to different parts of the body where they are used to build complex substances such as the proteins required by the body.
  his process is called assimilation.

Question 11.
What happens in cellular respiration?
Answer:

• In the cells, glucose, breaks down with the help of oxygen into carbondioxide and water.
• Energy is also released.
• The released energy is stored in a stable form to utilise for different cellular activities.

Question 12.
What happens to the undigested food material in the digestive system ?
Answer:

• The undigested food passes into the rectum, and remains there as semi-solid faeces.
• The faecal matter is removed through the anus from time to time.
• This is called egestion.

Question 13.
What is diarrhoea ? How can we save the patients of diarrhoea?
Answer:

• The passing of watery stool frequently is called diarrhoea.
• It may be caused by infection, food poisoning or indigestion.
• Because of excessive loss of water and salts, the patient even may die.
• Even before a doctor is consulted, the patient should be given plenty of boiled and cooled water with a pinch of salt and sugar dissolved in it.
• This is called Oral Rehydration Solution (ORS).

Question 14.
“Cellulose is not digested in humans” – Why ? State the reason?
Answer:

• Animals like horses, rabbits, etc., have a large sac like structure called caecum; between the oesophagus and the small intestine.
• The cellulose of the food is digested here by the action of certain bacteria.
  These kind of bacteria are not present in human digestive systems.

Question 15.
Write the steps involved in rumination?
Answer:

• Animals like cows, rabbits, horses, etc., quickly swallow the grass and store it in a part of stomach called rumen.
• Here, the food gets partially digested and is called cud.
• But, the cud returns to the mouth in small lumps and the animal chews it.
• This process is called “rumination” and these animals are called ruminants.

Question 16.
Draw a neat and labelled diagram of digestive system of a ruminant?
Answer:

Extra Questions of Nutrition in Animals Class 7

Question 1.
Describe different types of teeth and their functions.
Answer:
Teeth are four types. They are

1. Incisors
2. Canines
3. Premolars
4. Molars.

1. Incisors:

• Incisors are located in the front center of the mouth.
• They are four teeth in upper jaw and four teeth in lower jaw.
• These are chisel shaped teeth.
• Function: Bite of the food into pieces.

2. Canines:

• Canines are located either side of incisors.
• They are 2 in upper jaw and 2 in lower jaw.
• Canies are slightly more pointed them incisors.
• Function : Tearing of food.

3. Premolars:

• Premolars are located behind the canine.
• They are 4 in upper jaw and 4 in lower jaw.
• These teeth have two cusps and 1 or 2 roots.
• Function : Tearing and grinding of food.

4. Molars :

• These are located in the last part of the mouth.
• They are 6 in the upper jaw and 6 in the lower jaw. (including wisdom teeth)
• These molars have a large flat biting surface with 4 cusps and 2 or 3 roots.
• Function : Chewing and grinding food.

Question 2.
What precautions will you take to keep your digestive system healthy?
Answer:

• Washing hands before eating.
• Chewing food well.
• Drinking enough water.
• Avoiding to take junk foods, cool drinks etc.
• Being stress and strain free.
• Avoiding skipping meal.
• Avoiding bad habits like smoking, chewing of tobacco, drinking of alcohol.
• Practicing exercises and yoga.
• Taking good nutrition food.

Question 3.
How do Amoeba takes its food?
Answer:

• Amoeba has many small bubbles – like vacuoles in its cytoplasm.
• Amoeba pushes out one or more finger – like projections called pseudopodia fo movement and capture of food.
• Food vacuole forms around the captured food.
• Food get digested in it, absorbed into the cytoplasm and assimilates.
• Finally, undigested food is sent out by opening this vacuole out at the body surface

Question 4.
Where do the food eaten by us go ?
Answer:

• We take food in the form of solids or liquids.
• It goes to the digestive system, which is consisting of the alimentary canal an digestive glands.
• Food get’s digested in the digestive system.
• Digested food is absorbed by the blood.
• Blood transports digestive food to different parts of the body for assimilation.
• Undigested food will be ejected out of the body.

Question 5.
Write the names of steps and processes involved in Holozoic nutrition.
Answer:
The steps involved in holozoic nutrition are :

• Ingestion – Food is taken into the body.
• Digestion – Conversion of food into simple soluble forms.
• Absorption – Transfer of food to the blood.
• Assimilation – Absorbed food became the part of the body.
• Egestion – Removal of waste products and undigested food from the body.

Question 6.
How can you say that the nutrition in human beings is holozoic nutrition ? (OR) How does nutrition takes place in human beings?
Answer:

• Human beings take food in the form of solids or liquids.
• It get’s digested in the digestive system.
• Digested food is absorbed by the blood.
• Blood transports digested food to different parts of the body for assimilation.
• Undigested food will be ejected out of the body.
• So, the nutrition in human beings is holozoic nutrition.

Question 7.
Describe the construction of digestive system in human beings.
Answer:

• The digestive system in human beings consists of the alimentary canal and digestive glands.
• The total length of alimentary canal is about 9 meters.
• Its main parts are mouth, oral cavity/buccal cavity, oesophagus, stomach, small intestine, rectum and anus.
• The salivary glands, liver and pancreas are the digestive parts connected to the alimentary canal.

Question 8.
Describe the holozoic nutrition in human beings. (OR) Explain the differrent parts in the digestive system of human beings.
Answer:

• Human beings take food in the form of solids or liquids.
• It gets digested in the digestive system.
• The digestive system consists of the alimentary canal and digestive glands like salivary glands, liver, pancreas etc.

a) Ingestion :

• Mouth : Food is taken into the body through the mouth.
• Buccal cavity : It contains tongue, teeth and secretions of salivary. Food becomes paste here.
• Pharynx : It is the common chamber for both digestive track and respiratory track.
• Oesophagus: It is a muscular tubular structure that connects pharynx with stomach. Food goes into stomach in peristaltic motion.

b) Digestion :

• Stomach: It is a muscular sac like structure. Food is grinded well and mix mixed its juices. Proteins digestion starts in the stomach. Hydrochloric acid kills bacteria in the food in the stomach.
• Duodenum : It is the first part of the small intestine. Bile juice from liver, pancreatic juice from pancreas enters into it and helps in digestion.
• Small intestine : It is about six meter long. Digestion of food is completed here with the help of its juices.
  (Note: Digestion starts in mouth.)

c) Absorption :

• Small intestine: The inner wall of small intestine have thousands of finger – like outgrowths called villi. They absorb the digested food.
• Large intestine : It absorbs water and minerals from the undigested food.

d) Assimilation :
Blood : The absorbed food mix with blood. Blood transport it to all body parts for assimilation.

e) Egestion :

• Rectum : it is a storage point of undigested food.
• Anus : The undigested fecal matter removed through anus.

Question 9.
What is the reason for a choking sensation or hiccups ?
Answer:

• When food particles enter the wind pipe. The wind pipe carries air from nostrits to lungs.
• It runs adjacent to the food pipe.
• But inside the throat air and food share a common passage.
• During the act of swallowing, a flap like value closes the passage of the wind pipe and guides the food into the food pipe.
• If by chance, food particles enter the wind pipe, we feel choked, get hiccups or cough.

Case Based / Data – Based Questions

I. Read the following information carefully and answer the following questions.

Different ways of taking food
The mode of taking food into the body varies in different organisms. Bees and hummingbirds suck the nectar of plants, infants of human and many other animals feed on mother’s milk. Snakes like the python swallow the animals they prey upon. Some aquatic animals filter tiny food particles floating nearby and feed upon them.

Question 1.
Humming birds feed on …………
A) Insects
B) Small birds
C) Snakes
D) Nectar
Answer:
D) Nectar

Question 2.
The mode of intake of food by python and snakes is …………
A) Biting
B) Chewing
C) Swallowing
D) Siphoning
Answer:
C) Swallowing

Question 3.
The mode of intake of food by butterfly is …………
A) Biting
B) Chewing
C) Siphoning
D) Sponging
Answer:
C) Siphoning

Question 4.
Houseflies take their food by …………
A) Sponging
B) Sucking
C) Chewing
D) Swallowing
Answer:
A) Sponging

Question 5.
The mode of intake of food by aquatic animals by …………
A) Filtering the floating food particles
B) Biting
C) Chewing
D) Sponging
Answer:
A) Filtering the floating food particles

II. Read the following information carefully and answer the questions.

The food components gradually get digested as food travels through the various compartments. The inner walls of the stomach and the small intestine, and the various glands associated with the canal such as salivary glands, the liver and the pancreas secrete digestive juices. The digestive juices convert complex substances of food into simpler ones. The digestive tract and the associated glands together constitute the digestive system.

Question 1.
Digestive system includes …………
A) Digestive tract
B) Digestive glands
C) Teeth
D) A and B
Answer:
D) A and B

Question 2.
Hydrochloric acid is secreted in …………
A) intestine
B) large intestine
C) stomach
D) mouth
Answer:
C) stomach

Question 3
Liver secretes a digestive juice called …………
A) Bile
B) Salivary amylase
C) Hydrochloric acid
D) Pancreatic juice
Answer:
A) Bile

Question 4.
Bile juice is stored in …………
A) gall bladder
B) Pancreas
C) Liver
D) Small intestine
Answer:
A) gall bladder

Question 5.
Saliva is secreted in …………
A) Mouth
B) Small intestine
C) Stomach
D) Large intestine
Answer:
A) Mouth

III. Read the following information carefully and answer the questions below.

Have you observed cows, buffaloes and other grass eating animals chewing continuously even when they are not eating? Actually, they quickly swallow the grass and store it in a part of the stomach called rumen. Here the food partially digested and is called ‘cud’. But later the cud returns to the mouth in small lumps and the animal chews it. This process is called rumination and these animals are called ruminants.

Question 1.
Which of the following is a ruminant …………
A) Rabbit
B) Horse
C) Cow
D) All the above
Answer:
D) All the above

Question 2.
‘Cellulose’ is not digested in …………
A) Cow
B) Goat
C) Sheep
D) Mouth
Answer:
D) Mouth

Question 3.
Celiulose is digested in ruminants with the help of …………
A) Fungi
B) Bacteria
C) Virus
D) Algae
Answer:
B) Bacteria

Question 4.
The food is stored partially in ruminants is …………
A) Rumen
B) Stomach
C) Small intestine
D) Large intestine
Answer:
A) Rumen

Question 5.
Cellulose is digested in …………..
A) Stomach
B) Caecum
C) Small intestine
D) Large intestine
Answer:
B) Caecum

IV. Read the following information carefully and answer the questions given below.

Amoeba is a microscopic single-celled organism found in pond water. Amoeba has a cell membrane, a rounded, dense nucleus and many small bubble-like vacuoles in its cytoplasm. Amoeba constantly changes its shape and position. It pushes out one, or more finger-like projections, called pseudopodia or false feet for movement and capture of food.

Question 1.
Amoeba is a …………
A) Multicellular organism
B) Single-celled organism
C) Tissue grade organism
D) Single celled and aquatic organism
Answer:
D) Single celled and aquatic organism

Question 2.
Amoeba captures it’s food with the help of …………
A) Pseudopodia
B) Food vacuole
C) Nucleus
D) None of the above
Answer:
A) Pseudopodia

Question 3.
The type of nutrition in Amoeba is …………
A) Holozoic
B) Autotroph
C) Saprotroph
D) Parasitic
Answer:
A) Holozoic

Question 4.
Amoeba constantly changes it’s …………
A) Food
B) Shape
C) Pseudopodia
D) Nucleus
Answer:
B) Shape

Question 5.
Food is Amoeba is digested is …………
A) Food vacuole
B) Nucleus
C) Pseudopodia
D) Nucleus
Answer:
A) Food vacuole

Question 6.
Digestive juices are secreted into …………
A) Food vacuole
B) Nucleus
C) Pseudopodia
D) Cytoplasm
Answer:
A) Food vacuole