AP 8th Class Biology 3rd Lesson Questions and Answers Crop Production and Management

AP State Board new syllabus 8th Class Biology Guide 3rd Lesson Crop Production and Management Textbook Exercise Questions and Answers.

AP 8th Class Biology 3rd Lesson Questions and Answers Crop Production and Management

8th Class Biology 3rd Lesson Crop Production and Management Questions and Answers (Exercise)

I. Select the correct word from the following list and fill in the blanks.

float, water, crop, nutrients, preparation

a) The same kind of plants grown and cultivated on a large scale at a place is called ……………
Answer: crop.

b) The first step before growing crops is …………… of the soil.
Answer: preparation.

c) Damaged seeds would …………… on top of water.
Answer: float.

d) For growing a crop, sufficient sunlight and …………… and …………… from the soil are essential.
Answer: water, nutrients.

2. Match Items In column A with those in column B.

Column-A	Column-B
i) Kharif crops	a) Food for cattle
ii) Rabi crops	b) Urea and super phosphate
iii) Chemical fertilisers	c) Animal excreta, cow dung urin and plant waste
iv) Organic manure	d) Wheat, gram, pea
	e) Paddy and maize

Answer:

Column-A	Column-B
i) Kharif crops	e) Paddy and maize
ii) Rabi crops	d) Wheat, gram, pea
iii) Chemical fertilisersb) Urea and super phosphate	b) Urea and super phosphate
iv) Organic manure	c) Animal excreta, cow dung urin and plant waste

Question 3.
Give two examples of each.
a) Kharif crop
b) Rabi crop
Answer:
Examples of Kharif crop : paddy, maize, soyabean, groundnut Examples of Rabi crop : wheat, gram, pea, mustard and linseed

Question 4.
Write a paragraph in your own words on each of the following.
a) Preparation of soil
b) Sowing
c) Weeding
d) Threshing
Answer:
a) Preparation of Soil :

• It is the first step before growing a crop.
• It is very important to turn the soil and loosen it. For this, ploughing is done.
• This allows the roots to penetrate deep into the soil.
• The loose soil allows the roots to breathe easily even when they go deep into the soil.
• Turning and loosening the soil brings the nutrient rich soil to the top so that plants can use these nutrients.
• After ploughing with a plough, farmers used to level the fields with the help of a leveller.
• Levelling the field is beneficial for sowing and for irrigation.

b) Sowing

• The process of putting seeds in the soil is called sowing.
• The tool used traditionally for sowing seeds is shaped like a funnel.
• The seeds are filled into the funnel, passed down through two or three pipes having sharp ends. These ends pierce into the soil and place the seeds there.
• Now a days, the seed drill is used for sowing with the help of tractors.
• This sows the seeds uniformly at equal distance and depth. Seeds get çovered by soil after sowing.
  Sowing by using a seed drill saves time and labour.

c) Weeding :

• The undesirable plants that may grow naturally along with crops are called weeds. The removal of weeds from crop fields is known as weeding.
• Weeds affect the growth of the crop. They absorb water and nutrients more than the crop plants. They also compete for space and light with crop plants.
• Weeds decrease the yield of the crops.
• Generally, farmers do tilling before sowing of crops. This helps in uprooting and killing of weeds.
• Farmers remove weeds physically by uprooting or cutting them close to the ground from time to time.
• Farmers use Khurpi and seed drill to remove weeds.
• Farmers also use chemical to control weeds in crops. They are called weedicides.
  Example : 2,4-D. These weedicides are sprayed with the help of sprayers to kill weeds.

d) Threshing :

• The process of separating the grain seeds from the chaff is called threshing.
• Generally, it is done by winnowing.
• Now a days, threshing is done by a machine called “combine” which is a combination of harvester and thresher.

Question 5.
Explain how fertilisers are different from manure.
Answer:
The differences between fertiliser and manure:

Fertiliser	Manure
1) Fertiliser is a manmade inorganic salt.	1) Manure is a natural substance obtained by the decomposition of cattle dung and plant residue.
2) Fertilser is prepared in factories.	2) Manure can be prepared in the fields.
3) Fertiliser does not provide any humus to the soil.	3) Manure provides a lot of humus to the soil.
4) Fertilisers are very rich in plant nutrients like nitrogen, phosphorus and potassium.	4) Manure is relatively less rich in plant nutrients.
5) Excessive use of fertilisers has made the soil less fertile.	5) The use of manure improves soil texture as well as it’s water retaining capacity.
6) It causes water pollution.	6) It does not cause water pollution.

Question 6.
What is irrigation ? Describe the two methods of irrigation which conserve water.
Answer:

• The supply of water to crops at regular intervals is called irrigation.
• Modern method of irrigation like sprinklers and drip system help us to use water economically.
• Sprinkler system is more useful on the uneven land where sufficient water is not available.

• In sprinklers, when the water is allowed to flow through the main pipe under pressure with the help of a pump, it escapes from the rotating nozzles. It gets sprinkled on the crop, as if it is rotating.
• Sprinkler is very useful for lawns, coffee plantation and several other crops.
  In drip system, the water falls drop by drop directly near the roots.
• It is the best technique for watering fruit plants, gardens and trees.
• Sprinklers and drip system minimise wastage of water and they are considered as a boon to farmers having low water availability.

Question 7.
If wheat is sown in the Kharif season, what would happen ? Discuss.
Answer:

• Wheat is grown in Rabi season.
• It is a short night plant. Flowering in these plants require short nights.
• The best season for wheat crop is from short nights. December to March. It requires hot and humid condition to grow. So, if we grow humid condition to grow. So, if we grow wheat is Rabi season we get a high crop yield.
• If wheat is sown in Kharif, the weather is not favourable for its growth. The temperature in Kharif is not sufficient to seed formation.
• So, we get a low production of crop yield.

Question 8.
Explain how soil gets affected by the continuous plantation of crops in a field.
Answer:

• Continuous cultivation of crops makes the soil poor in nutrients.
• The soil becomes infertile.
• It does not get enough time to replenish the nutrients.
• Farmers have to add manure to the soil to replenish the soil with nutrients.

Question 9.
What are weeds ? How can we control them?
Answer:

• The undesirable plant that may grow along with the crops, are called weeds.
• Weeding is done by different methods by the farmers.
• Most of the weeds are uprooted at the time of tilling or ploughing. Those still remain after tilling are manually uprooted.
• It is better to root out the weeds before flowering.
• Farmers use Khurpi for cutting weeds close to the ground. They also use a seed drill to uproot weeds.
• Weeds are also controlled by using certain chemicals called weedicides. 2, 4-D is an example for weedicide. They kill only the weeds and do not damage crops.
• Weedicides are diluted and sprayed in the fields with the help of sprayers.

Question 10.
Arrange the following boxes in proper order to make a flow chart of sugarcane crop production.

Answer:

Question 11.
Complete the following word puzzle with the help of clues given below.
Down :
1) Providing water to the crops.
2) Keeping crop grains for a long time under proper conditions.
5) Certain plants of the same kind grown on a large scale.

Across :
3) A machine used for cutting the matured crop.
4) A rabi crop that is also one of the pulses.
6) A process of separating the grain from chaff.
Answer:
Down :
1) Irrigation
2) Storage
5) Crop

Across :
3) Harvester
4) Gram
6) Winnowing

Question 12.
How can we provide food to a large number of people in our country?
Answer:

• Food has to be produced on large scale.
• In order to provide food for a large population – regular production, proper management and distribution of food is necessary.

Question 13.
Why paddy can not be grown in winter season?
Answer:
Paddy requires a lot of water. Therefore, it is grown only in the rainy season.

Question 14.
Why are they kept like this ?
Answer:
Seeds of a few plants such as paddy are first grown in a nursery. When they grow into seedlings as they are transplanted to the field manually. Some forest plants flowering plants are also grown in the same way.

Question 15.
Why do some plants grow better than others?
Answer:
Continuous cultivation of crops makes the soil poor in nutrients. Farmers have to add manure to the fields to replenish the soil with nutrients. This process is called manuring. Insufficient manuring results in weak plants.

Question 16.
Have these other plants been planted purposely?
Answer:
No, they are not planted purposely. These undesired plants may grow along with crop plants naturally. These are called weeds.

Question 17.
Do weedicides have any effect on the person handling the weedicide sprayer?
Answer:

• Spraying of weedicides may effect the health of farmers. So, they should use these chemicals very carefully.
• They should cover their mouth and nose with a piece of cloth during spraying of these chemicals.

Question 18.
I saw my mother putting some dried neem leaves in an iron drum containing wheat. I wonder why?
Answer:

• Dried neem leaves prevent the attack of pests, insects; and micro organisms on stored food grains.
• So, dried neem leaves are used for storing food grains at home.

Extended Learning – Activities And Projects

Question 1.
Sow some seeds in the soil and arrange to water them by drip irrigation. Observe daily.
i) Do you think it can save water?
ii) Note the changes in the seed.
Answer:
i) Yes, it is the best technique for watering plants. In this method water is not wasted at all. It is a boon in region’s where availability of water is poor.
ii) Seed will begin to germinate.

Question 2.
Collect different types of seeds and put them in small bags. Label them.
Answer:
Student activity.

Question 3.
Collect pictures of some other agricultural machines and paste them in a file. Write their names and uses.
Answer:
i) Used to harvest the crop

ii) Used to separate grains from chaff

iii) Weeds harrow : It is used to remove weeds from the field.

iv) Paddy planter : It is useful for planting. Paddy seedling in large areas. It is easy to maintain distance sowing the seedlings. It is a time and money saving method.

v) Modern Tractor Seed drill: It is helped to sow seeds in 5 or 6 rows. It also covers the sown seeds with soil immediately with the help of a blade attached to it. It is a time saving and easiest way of sowing seeds.

vi) Iron leveller: It is used for levelling the soil. By levelling the soil water and nutrients can be reached to every part of the land.

vii) Winnowing machine : It is used separate the grain and chaff.

viii) Combine : It is a combination of harvester as well as a thresher.

Question 4.
Project Work
Visit a farm, nursery or a garden nearby. Gather information about
i) importance of seed selection.
ii) method of irrigation.
iii) effect of extreme cold and extreme hot weather on the plants.
iv) effect of continuous rain on the plants.
v) fertilisers/manure used.
Answer:
i) Good quality’seeds are to be selected for sowing. It is useful for better growth of the crop.

ii) a) Traditional methods of irrigation are

• Moat (Pulley System)
• Chain pump
• Dhekli
• Rahat (Lever system)

b) Now a days, farmers are using modern methods of irrigation to save water and minimise water wastage. They are

• Sprinkler system
• Drip system.

These methods are boon to regions where availability of water is poor.

iii) Extreme cold weather will freeze the water inside plants, so cells will burst due to the exapansion of water causing the plants to die. Extreme hot conditions make the plants to milt. Plants close their stomata to prevent water loss. When transpiration fails, plants will die.

iv) If the plant is growing in the well drained soil, then there is no difficulty for plants to survive.
But when the plant is growing in a water logging soil, heavy rain blocks the pores of the soil and the root system of the plants gets damaged. Continuous rains may also damage the leaves of the plants as they may get torn.

v)

• Improve the fertility of soil.
• Enhances the water holding capacity of the soil.
• Manure increases the number of friendly microbes.
• It improves the texture of the soil.

8th Class Biology 3nd Lesson Questions and Answers (Lab Activities)

Activity-1

How do you identify damaged seeds ?
Answer:

• Take a beaker and fill half of it with water.
• Put a handful of wheat seeds into it and stir thoroughly.
• Leave the beaker undistrubed for 10-15 minutes.

Observations: Few seeds float on top of water.
Inference: Damaged seeds become hollow and are lighter in weight. So, they float on water.

Activity-2

Write an activity to show that manure or fertilisers are needed for healthy growth of crops.
Answer:

• Take moong or gram seeds and germinate them. Select three equal sized seedlings.
• Now take three empty glasses and mark them A, B and C.
• To glass – A, add little amount of soil mixed with a little cow dung manure.
• In glass – B, put the same amount of soil mixed with a little urea.
• Take the same amount of soil in glass – C without adding anything.
• Now, pour the same amount of water in each glass and plant the seedlings in them.
• Keep them in a safe place and water them daily keep the glasses undistrubed for 7 – 10 days.

Observations: The seedlings planted in glass A and glass – B have shown better growth than the seedling in glass – C
Inference: Manures and fertilisers help the plants to grow better and get high yield of crops.

Activity-3

Complete the following table.

S.No.	Food	Sources
1.	Milk	Cow, buffalo, she-goat, she-camel…….
2.
3.
4.

Answer:

S.No.	Food	Sources
1.	Milk	Cow, buffalo, she-goat, she-camel.
2.	Meat	Fish, sheep, goat, prawns, poultry birds.
3.	Honey	Honey bees.
4.	Eggs	Hens, ducks, emu birds