AP State Syllabus 9th Class Social Studies Solutions 5th Lesson Biosphere
9th Class Social Studies 5th Lesson Biosphere Textbook Questions and Answers
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Life itself constitutes a separate sphere called ‘Biosphere’. Explain.
- The Earth is a unique planet, in that it has life.
- It is inhabited by countless forms of life from microscopic bacteria to great banyan trees and animals like lions and blue whales and of course human beings.
- The earth has a combination of land, air and water and a moderate temperature has made life possible on it.
- Various forms of life are not only related to the three spheres around them, but also to one another.
- They influence one another and they are part of a complete “food chain.”
- Hence geographers are of the opinion that “life itself constitutes a separate sphere called ‘Biosphere’.
Why is ecological crisis created in modern times? What are its effects?
- These days the increase in population creates great pressure on earth as well as its resources.
- To satisfy the needs of ever growing population systematic mining, cutting of forests, building of forests and fields and roads took place all over the earth.
- Burning of fossil fuels and release of enormous amounts of waste materials by industries contaminate air, water, and soil.
- For providing food for the ever growing population, there is a need for increase in agricultural production.
- Modern agriculture uses a large amount of chemical fertilizers and pesticides.
- The most frightening aspect of pollution due to modern agriculture is the increase in the levels of toxins in our food.
- This increasingly proves to be very harmful not only to humans but also to all types of life on earth.
- Since all living and non-living things on the earth are in one way or the other connected to each other, change affecting one, in due time affects all the others too. All these factors lead to ecological crisis.
Effects of ecological Grisis :
- If a particular species which feeds upon a particular kind of plant is exterminated, it would result in unchecked growth of that plant and it may intrude the area where other plants grow and disturb their growth.
- Many industries use chemicals and metals which flow into the rivers and streams. The metals like mercury are consumed by microorganisms in water and in turn beome the food of fishes. When human beings consume these fishes they too absorb some amount of mercury which is detrimental to their health.
- Farmers use Diclofenac to treat cattle; when the cattle die their flesh retains this chemical: When their flesh is consumed by vultures, diclofenac leads to kidney failure in them and they die.
Natural vegetation depends upon the climate of the place. Write different kinds of forests and climatic conditions of their existence?
a) Tropical Deciduous Forests :
- Tropical deciduous forests are the monsoon forests.
- These regions experience seasonal changes.
- Trees shed their leaves in the dry season to conserve water.
b) Tropical Evergreen Forests :
- These thick forests occur in the regions near the equator and close to the tropics.
- These regions are hot and receive heavy rainfall throughout the year.
- As there is no dry season, these trees do not shed their leaves altogether.
- This is why they are called evergreen forests.
c) Temperate Evergreen Forests :
- These forests are located in the mid latitudinal costal region.
- They are commonly found along the eastern margin of the continents.
d) Temperate Deciduous Forests :
- The temperate deciduous forests are found in higher latitudes.
- They shed their leaves in the dry season.
e) Mediterranean Vegetation :
- The west and the south west margins of the continents are covered by these forests.
- Mediterranean trees adapt themselves to dry summers with the help of their thick barks and wax coated leaves. These help them to reduce transpiration.
- These regions are marked for hot dry summers and dry summers and mild rainy winters.
f) Coniferous Forests :
- Coniferous forests are found in the higher latitudes of Northern hemisphere.
- These forests are found in abundance in the Himalayas.
g) Tropical Grasslands :
- These forests grow on either side of the equator up to tropics.
- This vegetation grows in the areas of moderate to low amount of rainfall.
h) Temperate Grasslands :
- These are found in mid-latitudinal zones and in the interior part of the continents.
- Usually the grass is very short and nutritious.
i) Thorny Bushes :
- These are found in the dry desert like regions.
- This vegetation cover is scarce here because of scanty rain and scorching heat.
j) Tundra :
- This vegetation is found in the polar region.
- The growth of natural vegetation is very limited here.
- Only mosses, lichens and very small shrubs are found here.
How can we protect natural resources?
Preservation of the natural environment is essential for maintaining community sustainability.
Communities must work to assure an adequate water supply to meet future needs.
2. Energy :
Energy should be consumed reasonably.
3. Air and climate :
Communities can preserve air quality by limiting or eliminating the discharge of harmful chemicals into the air and by minimizing the sources of air pollution.
4. Biodiversity :
Healthy wildlife should be supported through integrative approaches for, managing, protecting, and enhancing wildlife populations and habitats appropriate to their area and the atmosphere.
5. Land, forests, ecosystems should be provided protective measures. Thus we can protect natural resources.
Read the lesson and fill up the table.
Locate the following countries in the world map.
a) New Zealand
d) North America
Read the paragraph under the title ‘Depletion of Resources’ on page 57 and comment on it.
|Industrialisation, rapid population growth and urbanisation all have meant unprecedented exploitation of natural resources like minerals, forests, soil, water, air etc. besides sources of energy (coal, petroleum etc.) stored in the earth for billions of years. This has resulted in rapid deforestation and decline of reserves of minerals, oil and ground water. Many scientists have argued that the present way of life is not ‘sustainable’for if we use so much natural resources, nothing will be left for our children and grand children.|
Depletion of resources is the consumption of a resource faster than it can be replenished.
Use of either of these forms of resources beyond their rate of replacement is considered to be resource depletion.
Resource depletion is most commonly used in reference to farming fishings mining, water and fossil fuels.
Visit any nearby industrial establishment and observe the different kinds of smoke, liquid and Solid Wastes come*6uf of the cdrrtp’ourtd. FincTout from the nearby’residents about their impact on plants and animals. Based on the information collected, prepare a report and present in the class.
I have visited a cement factory and observed the following :
Cement manufacture causes environmental impacts at all stages of the process. These include air-borne pollution in the form of dust, gases, noise and vibration when operating machinery and during blasting in quarries, and damage to country side from quarrying. Environmental protection also includes the re-integration of quarries.
- CO2 emissions : Cement manufacturing releases CO2 in the atmosphere.
- Heavy metal emissions in the air.
- Heavy metals present in the clinker.
- Use of alternative fuels and by-products materials.
- Noise levels are easy to establish.
- Smoke released from the factory causes breathing problems in the local people.
- Waste liquids are sent to the nearest river and pollute the river water.
Collect the details of some endangered animals and birds in your area. Fill the following table. Discuss in the classroom. Take the help of your elders and teachers.
9th Class Social Studies 5th Lesson Biosphere InText Questions and Answers
Can you say how plants are dependent upon air and water and how they affect the two in return? (Text Book Page No. 51)
- Plants need water. Plants use water to carry moisture and nutrients from the roots to the leaves and food from the leaves back down to the roots.
- Plants absorb carbon dioxide from air to form carbohydrates during the process of photosynthesis.
- Nitrogen gas molecules that are trapped and carried in the water droplets provide nourishment to plants.
- Plants need oxygen in small amounts in respiration.
- Plants reduce the carbon dioxide levels in atmosphere and reduce the greenhouse effect and in turn the global warming.
How do plants affect water and air in return?
- Plants return water to the atmosphere through the process of transpiration.
- Transpiration is the evaporation of water from aerial parts of plants, especially from . leaves but also from stems and flowers.
In what ways are insects like mosquitoes and butterflies dependent upon rocks or soil and upon water ? How do they affect them in return? (Text Book Page No. 51)
Many insects depend on soil for part of their life. They make their home in the soils. Some insects live some portion of their lives in water.
Insects get involved lot of biological processes. Among the most significant beneficial impacts of insects on soil are
- Their role in regulation of pest populations,
- The pollination of crops and
- The soil engineering. Insects mostly pollute the water.
Identify the desert regions in the world map.
- The Sahara Desert
- The Kalahari Desert
- The Thar Desert
- The Arabian Desert
- The Australian Desert
- The Atacama Desert
- The Sonaran Desert
Look around in your surroundings and find out the articles made of hard wood and soft wood. (Text Book Page No. 55)
A) Articles made of hard wood :
- Hard woods are often used to make items including furniture, flooring and utensils. Spoons, chopsticks, bowls, plates and cups are the utensils made from hard wood.
- Musical instruments such as violins, guitars, pianos and hard drums are also made of hard wood.
- Sofas, chairs, beds, benches, tables and wardrobes are made of hard wood.
B) Articles made of soft wood :
Manufacturing paper, newsprint, decorative articles, carvings, dolls, match boxes and packing boxes, etc. are made from soft wood.
Find out and learn few names of trees of your locality. (Text Book Page No. 55)
In our local we can see Neem trees, Mango trees, Banyan trees and the trees are known by their local names: Chinta, Tumma, Seema Tumma, Palm (Tati), Bandaru, Yegisa are the trees which give us wood.
The trees such as Bamboo give us pulp.
Mangoes, Guavas, Blackberry are fruit bearing trees. In addition to them we have coconut trees and trees which give us drumsticks.
Can you discuss how human beings would have impacted the land, water, plants and animals around them when they began agriculture and animal herding? (Text Book Page No. 56)
- With the development of agriculture humans began to radically transform the environment in which they lived.
- They cleared the lands around their settlements and controlled the plants that grew and the animals that grazed on them.
- They devised ways of storing rain water and rechanneling river water to irrigate plants.
- They built reservoirs, dug canals, dikes and sluices that permitted water storage.
- They domesticated major food crops, plants such as flax and cotton and began to cultivate them.
- Men also took lead in taming, breeding and raising the large animals associated with both farming and pastoral communities.
- Thus human beings impacted the land water, plants and animals around them when they began agriculture and animal rearing.
What sources of energy would they have used and how would they haveobtained them? (Text Book Page No. 56)
- The growth of sedantary farming greatly accelerated the pace of technological and social change.
- Still the man used the physical energies of human and animals to use the agricultural and manufacturing tools.
- He used wheel to make pots, plough to plough his fields and boats to transport his goods and kiln of blacksmith to make his tools.
- He burnt firewood to cook his food.
- Thus when they began agriculture man used merely the physical energy of human beings and animals.
Can you say what kinds of changes will building of cities have on the land and water around them? (Text Book Page No. 56)
- With the beginning of agriculture and use of better tools give rise to larger, more elaborate and commodious housing and the construction of community ritual centres.
- Sun-dried bricks, interwoven branches usually plastered with mud and stone structures were associated with early agricultural communities.
- Houses in early agricultural settlements included special storage areas. They were centered on clay or stone hearths that were ventilated by a hole in the roof.
- To defend their cities from the rival nomadic settlements, they fortified their cities.
- The people had devised ways of storing rain water and rechanneling river water to irrigate plants.
- The reservoirs and canals, dikes and sluices that permitted water storage were constructed.
In what way do you think this would have affected the land scape and water cycle? (Text Book Page No. 56)
- The increase in population create great pressure on earth as well as its resources.
- The entire earth was reshaped to suit the needs of humans.
- The surface of the earth received a great push with the industrial revolution and process of colonization.
- Industrial production needs raw materials on an unprecedunted scale.
- Industrial countries began to search for diverse kinds of raw materials and sources of energy.
- They dug deep wells and tried to find out what lay underneath.
- Systematic mining, cutting of forests, building of factories and fields and roads took place all over the world.
- The cumulative impact of industrial pollution causes greenhouse effect and global warming.
- The greenhouse effect could cause decrease in precipitation and soil moisture content and decrease of snow cover and finally decrease in rainfall.
- The increased surface temperature would cause melting of glaciers and lead to flooding of coastal areas.