Sunday, May 3, 2020

Science Class 8 Solutions Chapter 1 Crop Production and Management


Science Class 8 Solutions Chapter 1 Crop Production and Management

Question 1.
Which agricultural practice is carried out with the help of a sickle?
Answer:
Sickle: A sickle is a hand-held agricultural tool used for harvesting, or reaping crops (as shown below)
Lakhmir Singh Science Class 8 Solutions Chapter 1 Crop Production and Management sh Q 1
Harvesting in our country is either done manually by sickle or by a machine called harvester. The other agricultural practices which are done by sickle are: preparing hay and also cutting some crops.
Question 2.
What name is given to the cutting and gathering of a food crop like wheat or paddy?
Answer:
The cutting and gathering of mature food crop like wheat or paddy is known as harvesting.
Question 3.
Name the tool (or implement) used in the traditional harvesting of crops.
Answer:
Sickle is general purpose of harvesting tool which is used in the traditional harvesting of crops.
Question 4.
Name the process of beating out the grains from harvested crop.
Answer:
The process of beating out the grains from the harvested crop plants is called threshing.
Question 5.
Name the machine used in recovering the grain from already cut crop.
Answer:
A machine called combine is used for harvesting and threshing (Cutting of standing crop and recovering grains).
Question 6.
Name the machine which does the cutting of standing crops and recovers the grain too.
Answer:
A machine called combine is used for harvesting and threshing (Cutting of standing crop and recovering grains).
Question 7.
Name the process in which grains are separated from chaff and hay with the help of wind.
Answer:
The process in which grains are separated from chaff with the help of wind is called winnowing.
Question 8.
Name three food materials obtained from animals.
Answer:
The food materials that we obtain from animals are milk, meat and eggs.
Question 9.
Name two domestic animals which are used to obtained milk.
Answer:
Cow and buffalo are two domestic animals which are used to obtained milk.
Question 10.
Name one meat yielding animal and one egg yielding animal.
Answer:
Goat is meat yielding animal and hen is egg yielding animal.
Question 11.
Name an animal food obtained from insect.
Answer:
Honey is an animal food obtained from insect called “bees”.
Question 12.
What name is given to that branch of agriculture which deals with feeding, shelter, health and breeding of domestic animals?
Answer:
The branch of agriculture which deals with feeding, shelter, health and breeding of domestic animals is called animal husbandry.
Question 13.
Name one major food nutrient provided by fish.
Answer:
Fish is good for health. We get cod liver oil from fish which is rich in vitamin D.
Question 14.
Name the vitamin/vitamins present in cod liver oil.
Answer:
Cod liver oil of fish is rich in vitamin D.
Question 15.
Name one Government agency which is involved in procuring food grains (like wheat and rice) from farmers and storing them properly.
Answer:
The government agency like food corporation of India (FCI) buy food grains from farmers and storing them properly.
Question 16.
What type of organisms grow on stored food grains having higher moisture content?
Answer:
Organisms fungus and moulds grow on stored food grains having higher moisture content.
Question 17.
Which crop is generally grown between two cereals crops in crop rotation to restore the fertility of soil?
Answer:
Leguminous crops like pulses, beans, peas are generally grown between two cereals crops in crop rotation to restore the fertility of soil.
Question 18.
State one advantages of growing a leguminous crop between two cereals crops.
Answer:
Rotation of crops (leguminous and non-leguminous crops) in the same field replenishes the soil with nitrogen naturally and increases the soil fertility.
Question 19.
Name the nitrogen-fixing bacteria present in root nodules of leguminous plants.
Answer:
The nitrogen-fixing bacteria present in root nodules of leguminous plants is rhizobium bacteria.
Question 20.
Which agricultural practice comes first: harvesting or weeding?
Answer:
Agricultural practice weeding comes first.
Question 21.
Which is the first step in the cultivation of a crop?
Answer:
The preparation of soil is the first step in the cultivation of a crop.
Question 22.
For what purpose is a hoe used?
Answer:
It is a simple tool which is used for removing weeds and for loosening the soil.
Question 23.
Name the implement used in sowing.
Answer:
The implement used for sowing is seed drill.
Question 24.
Name the practice used for cultivating paddy.
Answer:
The practice used for cultivating paddy is transplantation.
Question 25.
Name the two types of substances which are added two the fields by the farmers to maintain the fertility of soil.
Answer:
Manure and fertilizers are added to the fields by the farmers to maintain the fertility of soil.
Question 26.
Some grass is growing in a wheat field. What will it be known as?
Answer:
These grass is known as weed.
Question 27.
Name one crop which can tolerate standing water (water-logging) in the field and one which cannot.
Answer:
Paddy crop (rice crop) can tolerate standing water in the field whereas crops like wheat, gram cannot.
Question 28.
Which is the best time for the removal of weeds?
Answer:
The best time for the removal of weeds is before they produce flowers and seeds.
Question 29
Name two methods of irrigation with conserve water.
Answer:
1. sprinkler system
2. Drip system
Question 30
Fill in the following blanks:
(a) The same kind of plants grown and cultivated on a large scale at a place is called ………………….
(b) The first step before growing crops is ……._……..of soil.
(c) For growing a crop, sufficient sunlight, ………., and …………. from the soil are essential.
(d) Damaged seeds would ……….. on top of water.
(e) Crop rotation helps in the replenishment of soil with …………..
(f) The supply of water to crops at different intervals is called …………..
(g) The unwanted plants present in a crop field are called……………
(h) Dried…………..leaves are used for storing food grains at home.
(i) Many people living in the ……….areas consume fish as a major part of their diet.
Answer:
(a) crop
(b) preparation
(c) nutrients; water
(d) float
(e) nitrogen
(f) irrigation
(g) weeds
(h) neem
(i) coastal
Lakhmir Singh Science Class 8 Chapter 1 Short Answer Type Questions
Question 31 A.
Why is it is necessary to dry the harvested food grains before storage ?
Answer:
The fresh crop has more moisture. So, the food grains obtained by harvesting the crop are dried before storage. If freshly harvested food grains are stored without drying, they may get spoilt or attacked by organisms, losing their germination capacity.
Question 31 B.
What are the two ways in which farmers store food grains ?
Answer:
The farmers store food grains in jute bags and metal bins at home.
Question 32.
Out of drip system and sprinkler system of irrigation, which one is more suitable :
(a) for uneven land?
(b) for sandy soil?
(c) for watering fruit plants ?
(d) where availability of water is poor?
Answer:
(a) Sprinkler system is more suitable for uneven land where sufficient water is not available.
(b) Sprinkler system is very useful for sandy soil.
(c) Drip system is best technique for watering fruit plants, gardens and trees.
(d) Drip system of irrigation is more suitable where availability of water is poor.
Question 33 A.
What are weeds? Name any one weed found in a crop field.
Answer:
The undesirable plants which grow along with a cultivated crop are called weeds. Wild oat is a weed which is found in wheat crop field.
Question 33 B.
How do weeds affect the growth of crops?
Answer:
Weed compete with the crop plants for water, nutrients, space and light. Thus, they affect the growth of crops.
Question 34.
Explain how, the irrigation requirements depend on the nature of the crop.
Answer:
Proper watering of crop at right time is called irrigation. Each crop needs a specific amount of water during its various stages of its growth. The irrigation requirements depend on the nature of crop. Some crops like paddy crop (rice crop) need more water whereas other crops like wheat, gram require less water.
Question 35.
Explain how, the irrigation requirements of a crop depend on the nature of soil in which the crop is grown.
Answer:
The irrigation requirements of a crop depend on the nature of soil in which the crop is grown. There are two types of soil- sandy soil and clayey soil. Sandy soil is highly porous having highly permeability. So, the water quickly percolates down to the soil and crop plants standing in the sandy soil, are not able to get adequate amount of water. Thus, crop cultivated in sandy soil need more frequent irrigation of water. On the other hand, the clayey soil is much less permeable than sandy soil due to which it can retain water for a much longer time. Thus, crop cultivated in clayey soil can absorb adequate amount of water. Hence, the crop grown in a clayey soil need irrigation less frequently.
Question 36.
Describe the sprinkler system of irrigation. State its advantages.
Answer:
In the sprinkler system of irrigation, a main pipeline is laid in the field. The perpendicular pipes, having rotating nozzles on top, are joined to the main pipeline at regular intervals. When 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 raining.
Advantages of sprinkler system of irrigation:
1. This system is more useful on the uneven land where sufficient water is not available.
2. This system is also very useful for sandy soil.
Question 37.
Explain the drip system of irrigation. State two advantages of the drip system of irrigation.
Answer:
In this system, there is a network of narrow pipes with small holes, in the fields. When water flows through these pipes, water falls drop by drop just at the position of the roots. So, it is called drip system. Water is not wasted at all. It is the best technique for watering fruit plants, gardens and trees.
Advantages:
1. Drip system is very useful in those regions where availability of water is poor.
2. Drip system provides water to plants drop by drop. So, water is not wasted at all.
Question 38.
How do the irrigation requirements of a wheat crop differ from that of a paddy crop ?
Answer:
Each crop needs a specific amount of water during its various stages of its growth. The irrigation requirements depend on the nature of crop. Some crops like need more water whereas other crops require less water. For example, paddy crop requires continuous irrigation whereas wheat crop requires less water.
Question 39.
Explain why, the frequency of irrigation of crops is higher in summer season.
Answer:
The frequency of irrigation of crops is higher in summer season due to the increased rate of evaporation of water from the soil and the leaves.
Question 40.
How are weeds removed from the crop fields ? Name one implement used for weeding.
Answer:
The removal of weeds from the crop fields is known as weeding. It is necessary process as weed competes with the crop plants for water, nutrients and space. Farmers adopt many ways to remove weeds and control their growth. The various ways by which weeds are removed from the crop fields are-
1. With hand – In this method, weeds are removed manually by uprooting or cutting them close to the ground.
2. By using a khurpa – In this method, weeds can be removed by using a implement called khurpa.
3. By using weedicides- Example- 2, 4-D
Question 41.
If wheat is sown in the kharif season, what would happen? Discuss.
Answer:
If wheat is sown in the kharif season, it will not grow well as plants cannot tolerate too much water of the rainy season.
Question 42.
Which of the following are kharif crops and which are rabi crops ? Wheat, Paddy, Gram, Maize, Mustard, Cotion, Soyabean, Linseed, Peas, Groundnut
Answer:
Kharif crops
Rabi crops
Paddy

Wheat

Maize

Gram

Cotton

Mustard

Soyabean

Linseed

Groundnut

Peas

Question 43.
What is a crop? Give two examples of crops.
Answer:
When plants of the same kind are grown and cultivated at one place on a large scale, it is called a crop. Examples- Wheat and Maize.
Question 44.
What are the two types of crops based on seasons ? Give one e ample of each type.
Answer:
Based on seasons, all crops are classified into two main groups:
1. Kharif crops- The crops which are sown in the rainy season are called kharif crops. Example- paddy, maize.
2. Rabi crops – The crops grown in winter season are called rabi crops. Examples- wheat, gram, etc.
Question 45.
Name the various agricultural practices in the right sequence in which they are undertaken by the farmers.
Answer:
The various agricultural practices which they are undertaken by the farmers are:
1. Preparation of soil
2. Sowing
3. Adding manure and fertilisers
4. Irrigation
5. Protecting from weeds
6. Harvesting
7. Storage
Question 46.
Describe briefly, how soil is prepared for sowing the seeds.
Answer:
The preparation of soil is the first step before growing a crop. The soil is prepared for sowing the seeds of crop by ploughing, levelling and manuring. The process of loosening and turning the soil is called ploughing. It is done by using a tool called plough. It is made up of wood or iron. One of the important task in agriculture is to turn the soil and loosen it. It allows the roots to penetrate deep into the soil so that plants are held more firmly to the soil. The ploughed field may have big pieces of soil called crumbs. It is necessary to break these crumbs with a plank. The levelling of ploughed soil is done by using an implement called leveller. Sometimes, manure is added to the soil before tilling. This helps in proper mixing of manure with soil. Once the soil is ploughed, levelled and manured, it is ready for sowing of seeds.
Question 47.
Why do farmers carry out levelling of the ploughed fields?
Answer:
Top layer of soil supports plant growth. It gets loss due to ploughing because of which it can easily washed away by rain or blown away by wind. So, ploughed soil is levelled by pressing it with a wooden leveller, so that top soil is not blown away by wind or washed away by water.
Question 48.
What are the advantages of sowing seeds. with a seed drill?
Answer:
Following are the advantages of sowing seeds with a seed drill:
1. Seed drill sows the seeds uniformly at proper distance and correct depths.
2. It sows the seeds in regular rows.
3. It ensures that seeds get covered by the soil after sowing as a result of which seeds cannot be picked by birds
4. Sowing by using a tractor joined with seed drill saves time and labor.
Question 49.
Explain why, the seeds should be sown at right spacings.
Answer:
Seeds should be sown at right spacings. They should be neither sown too close nor too far apart. If seeds are placed too close, then plants formed form them will be also too close and will not get enough sunlight, water and nutrients to grow. On the other hand, if seeds are placed too far, then it will be a wastage of field space. Thus, the seeds should be sown at right spacing to proper growth.
Question 50.
What is ploughing (or tilling)? Name any two implements used for tilling the fields.
Answer:
The process of loosening and turning the soil is called ploughing or tilling. The agricultural implements used for tilling (loosening and turning) the soil are plough and hoe.
Question 51.
State two beneficial effects of – ploughing the fields (or loosening and turning the soil).
Answer:
Loosening and turning the soil is very important for cultivation of crops. The loosening and turning the soil by ploughing is beneficial because of the following reasons:
1. The loose soil allows the roots to breathe easily even when they go deep into the soil.
2. The loosened soil helps in the growth of earthworms and microbes present in the soil.
Question 52 A.
State the function of Food Corporation of India.
Answer:
The government agency like food corporation of India (FCI) buy food grains from farmers and storing them properly so that they can be supplied throughout the country.
Question 52 B.
What is done to protect tile grains stored in gunny bags in big go downs from damage ?
Answer:
Pesticide solution are sprayed on the gunny bags in big go downs from time to time to protect the grains from damage.
Question 53.
Define manure. What are the advantages of manure ?
Answer:
Manure is an organic substance obtained by the decomposition of plants or animals wastes.
Advantages of manure:
·         it enhances the water holding capacity of the soil.
·         it makes the soil porous due to which exchange of gases becomes easy.
·         it increases the number of friendly microbes.
·         it improves the texture of the soil
Question 54.
What is a fertilizer ? Name any two fertilizers. State two harmful effects caused by the excessive use of fertilizers.
Answer:
Fertilisers are chemical substances which are rich in a particular nutrient. Some examples of fertilizers are urea, potash, NPK (nitrogen, phosphorus, potassium), etc.
Harmful effects caused by the excessive use of fertilizers are-
1. Excessive use of fertilizers makes the soil less fertile.
2. Excessive use of fertilizers causes water pollution.
Question 55.
Explain how, soil gets affected by the repeated growing of croping the same fields. How does use of fertilizers help the farmers ?
Answer:
Plants require nutrients for their proper growth and functioning. If continuous plantation of crops is done in the fields then the soil will become poor in necessary nutrients like nitrogen, phosphorus, potassium, etc. This affect the yield and also affects the quality of soil. So, the nutrients once consumed by crop must be replenished so that soil get all its nutrients back and it will be ready for the next harvest.
Fertilizers help the farmers to get better yield of crops such as wheat, paddy and maize.
Question 56.
What is weeding? Why is weeding necessary ?
Answer:
The removal of weeds is called weeding. Weeding is necessary since weeds compete with the crop plants for water, nutrients, space and light. Thus, they affect the growth of the crop. Some weeds interfere even in harvesting and may be poisonous for animals and human beings.
Question 57.
What are weedicides? Name one weedicide.
Answer:
Weedicides are special chemicals which are used to control weeds. 2,4-D is an example of weedicide.
Question 58.
What precaution should be taken while spraying weedicides ? Why
Answer:
Weedicides affects the health of farmer. So, weedicides should be used vary carefully. During spraying of weedicides, the nose and mouth of farmer should be covered with a piece of cloth.
Question 59.
Give any four differences between manures and fertilizers.
Answer:
Differences between manures and fertilizers:
Manure
Fertilizer
It is natural substance obtained from decomposition of plant or animal wastes.
It is a chemical substance which is rich in a particular nutrient.
It can be prepared in the fields.
It is prepared in the factories.
It is not very rich in plant nutrients like nitrogen, phosphorus, potassium.
It is very rich in plant nutrients like nitrogen, phosphorus, potassium.
It provides lots of humus to the soil.
It does not provide any humus to the soil.
Question 60.
Define the terms:
1. harvesting,
2. threshing, and
3. winnowing.
Answer:
1. Harvesting: The cutting and gathering of mature food crop like wheat or paddy is known as harvesting.
2. Threshing: The process of removal of the grains of harvested crop from the chaff is called threshing.
3. Winnowing: The process in which grains are separated from chaff with the help of wind is called winnowing.
Question 61 A.
What are the two ways in which food grains are stored on a large scale?
Answer:
Food grains are stored on a large scale in silos and granaries (gunny bags).
Question 61 B.
What is the advantage of storing food grains in gunny bags?
Answer:
The advantage of storing food grains in gunny bags is that food grains filled in gunny bags can be easily transported and distributed at various parts of country.
Question 62.
Name two traditional methods of irrigation and two modem methods of irrigation.
Answer:
Traditional methods of irrigation are chain pump and dhekli.
Modern methods of irrigation are sprinkler and drip system.
Question 63.
What is a ‘combine’ which is used in agriculture ? State its functions.
Answer:
The process of threshing is done with the help of a machine called combine. It is in fact a combined harvester and thresher.
Combine separates the grains from chaff.
Question 64.
What is ‘animal husbandry’?
Answer:
The branch of agriculture which deals with feeding, shelter, health and breeding of domestic animals is called animal husbandry.
Question 65.
What are the various practices necessary for raising animals for food and Other purposes.
Answer:
The various practices necessary for raising animals for food and Other purposes are:
·         Proper food of animals,
·         Proper shelter of animals, and
·         Proper care of animals.
Lakhmir Singh Science Class 8 Chapter 1 Long Answer Type Questions
Question 66 A.
What is meant by kharif crops ? Give two examples of kharif crops.
Answer:
Kharif crops- The crops which are sown in the rainy season are called kharif crops. The rainy season in India is generally from June to September. Example- paddy, maize.
Question 66 B.
What is meant by rabi crops ? Give two examples of rabi crops.
Answer:
Rabi crops – The crops grown in winter season are called rabi crops. The winter season in India is generally from October to March. Examples- wheat, gram, etc.
Question 67 A.
What is meant by ‘sowing’? What are the various methods of sowing the seeds?
Answer:
Sowing is the process of putting the seeds in the soil. There are two methods of sowing the seeds in the soil. These are-
1. Sowing by hand, and
2. Sowing with a sand drill.
Question 67 B.
What precautions should be taken in sowing the seeds?
Answer:
Following precautions should be taken while sowing the seeds in the soil:
1. The seeds should be sown at right depth in the soil suitable for germination.
2. The seeds should be sown at proper spacing.
3. The seeds should not be sown in highly wet soil.
4. The seeds should not be sown in a dry soil.
Question 68.
What are good quality seeds? You are given a sample of wheat seeds. How will you select good, healthy seeds for sowing ?
Answer:
Good quality seeds basically mean the most competent seeds, which will definitely give rise to a healthy plant, which would bear more healthy seeds. This is important when you’re dealing with plants at a large scale, and you need to maintain crops for a large​ time frame.
Best wheat seeds would be ones who’s color, shape and size are normal (not brownish, oddly shaped, tiny or bloated). Apart from just the looks, seeds are also tested for their efficiency in germination (how many seeds from set of 100 would grow in plants when sowed).
Question 69 A.
What is the process of ‘transplantation’ in agriculture? Give examples of two crops which are usually grown by this process.
Answer:
The process of transferring the seedlings from the nursery to the main field by hand is called transplanting or transplantation. Some crops like paddy and many vegetables, the seeds are not directly sown in the field’s soil. In these crop, initially the seeds are sown in the small nursery to obtain seedlings. Seedlings are then transplanted into the regular fields placing them at a proper distance from one another.
The practice of transplantation is used in the cultivation of paddy crop and many vegetables like tomatoes and chillies.
Question 69 B.
State two advantages of the process of transplantation in growing crops.
Answer:
Advantages of transplantation in growing crops:
1. The process of transplantation helps in planting seedling at a proper distance from one another so that plants can get obtain adequate amount of water, nutrients and sunlight.
2. The process of transplantation helps to select only healthy seedlings for the cultivation of crops.
Question 70 A.
What is irrigation? Why is irrigation necessary?
Answer:
The supply of water to crops at right time is called irrigation. All the crop plants need water for their growth. Water is important for proper growth and development of flowers, fruits and seeds of plants.
Irrigation is necessary for the absorption of nutrients by plants from the soil. Water is absorbed by the plant roots. Along with water, minerals and fertilizers are also absorbed.
Irrigation is necessary to provide moisture for germination of seeds because germination of seeds does not take place under dry conditions.
Irrigation is also necessary for healthy crop growth so as to get good yield. Nutrients dissolved in water get transported to each part of the plant. Water also protects the crop from both frost and hot air currents.
Question 70 B.
Name the various sources of irrigation in our country.
Answer:
The various sources of irrigation in our country are- wells, tubewells, ponds, lakes, rivers, dams and canals.
Lakhmir Singh Science Class 8 Chapter 1 Multiple Choice Questions (MCQs)
Question 71.
Which of the following crops would enrich the soil with nitrogen?
A. apple
B. pea
C. paddy
D. potato
Answer:
B. pea
The nitrogen-fixing bacteria present in root nodules of leguminous plants is rhizobium bacteria. Rotation of crops (leguminous and non-leguminous crops) in the same field replenishes the soil with nitrogen naturally and increases the soil fertility.
Question 72.
Which of the following is not a kharif crop?
A. paddy
B. mustard
C. maize
D. groundnut
Answer:
B. mustard
The crops which are sown in the rainy season are called kharif crops. The rainy season in India is generally from June to September. Example- paddy, maize.
Question 73.
In agriculture, broadcasting is used for:
A. ploughing the fields
B. rotating the crops
C. Removing the weeds
D. sowing the seeds
Answer:
D. sowing the seeds
The sowing of seeds by hand is called broadcasting.
Question 74.
Fish liver oil is rich in :
(A) Vitamin A
(B) Vitamin B
(C) Vitamin C
(D) Vitamin D
A. A and B
B. B and C
C. A and D
D. only D
Answer:
C. A and D
Fish liver oil is rich in both vitamin A and vitamin D.
Note: (If you have to choose just one Answer:, select Vitamin D like in case of MCQs)
Question 75.
Which of the following is not grown by transplantation?
A. chillies
B. tomatoes
C. peas
D. paddy
Answer:
C. peas
The process of transferring the seedlings from the nursery to the main field by hand is called transplanting or transplantation. Some crops like paddy and many vegetables like tomatoes and chillies, the seeds are not directly sown in the field’s soil.
Question 76.
Which of the following is not a rabi crop?
A. soyabean
B. peas
C. wheat
D. linseed
Answer:
B. peas
The crops grown in winter season are called rabi crops. Examples- wheat, gram, etc.
Question 77.
One of the following crop is not cultivated by sowing its seeds directly into soil. This one is:
A. wheat
B. gram (charm)
C. paddy
D. maize (makka)
Answer:
C. paddy
The process of transferring the seedlings from the nursery to the main field by hand is called transplanting or transplantation. Some crops like paddy and many vegetables, the seeds are not directly sown in the field’s soil.
Question 78.
Tomatoes are cultivated by the practice called:
A. transpiration
B. translocation
C. transportation
D. transplantation
Answer:
D. transplantation
Paddy, tomatoes and chillies are grown by transplantation.
Question 79.
Which of the following cannot be provided to the soil by a chemical fertilizer?
A. nitrogen
B. humus
C. potassium
D. phosphorus
Answer:
B. humus
Nitrogen, phosphorus and potassium are chemical which can be provided to the soil by chemical substance called fertilizers whereas humus cannot. It is provided to the soil by natural substance called manure.
Question 80.
Which of the following is not grown by transplantation?
A. chillies
B. tomatoes
C. paddy
D. papaya
Answer:
D. papaya
Paddy, tomatoes and chillies are grown by transplantation.
Question 81.
The Rhizobium bacteria present in the root nodules of pea plants can fix one of the following from the atmosphere. This one is:
A. hydrogen
B. oxygen
C. nitrogen
D. halogen
Answer:
C. nitrogen
The Rhizobium bacteria present in the root nodules of pea plants can fix nitrogen.
Question 82.
The process of beating out grains from the harvested wheat crop is called:
A. beating
B. crushing
C. threshing
D. weeding
Answer:
C. threshing
The process of beating out grains from the harvested wheat crop is called threshing. It is done by a machine called combine.
Question 83.
The food obtained from animals is very rich in:
A. fats
B. carbohydrates
C minerals
D. proteins
Answer:
D. proteins
The food obtained from animals is very rich in proteins.
Question 84.
The Government Agency responsible for purchasing grains from the farmers, safe storage and distribution is
A. CBI
B. FBI
C. FCI
D. FDI
Answer:
C. FCI
The government agency like food corporation of India (FCI) buy food grains from farmers and storing them properly.
Question 85.
the process of removing unwanted plants from a crop field is called?
A. Breeding
B. weeding
C. transplanting
D. harvesting
Answer:
B. weeding
The removal of unwanted plants called weeds is called weeding.
Question 86.
Poultry gives us:
A. eggs
B. meat
C. meat as well as eggs
D. honey
Answer:
C. meat as well as eggs
Poultry gives us meat as well as eggs.
Question 87.
Which of following is not a correct statement for sowing seeds?
A. seeds should be sown at right intervals
B. seeds should be sown at right depth
C. seeds should be sown in dry soil
D. seeds should not be sown in highly wet Soil
Answer:
C. seeds should be sown in dry soil
Seeds should not be sown in dry soil because water is necessary for germination of seeds.
Question 88.
Which of the following system of irrigation is preferred for the uneven land?
A. chain pump irrigation system
B. drip irrigation system
C. sprinkler irrigation system
D. river irrigation system
Answer:
C. sprinkler irrigation system
Sprinkler system is more suitable for uneven land where sufficient water is not available.
Question 89.
The two crops which are not grown by sowing their seeds directly into the soil in large fields are:
(A) Peas
(B) Tomatoes
(C) Chillies
(D) Maize
A. A and B
B. B and C
C. A and C
D. only C
Answer:
B. B and C
The two crops which are not grown by sowing their seeds directly into the soil in large fields are tomatoes and chillies.
Question 90.
The best Technique of Watering the fruit plants and Tree is:
A. chain pump system
B. sprinkler system
C. moat (pulley system)
D. drip system
Answer:
D. drip system
In this system, there is a network of narrow pipes with small holes, in the fields. When water flows through these pipes, water falls drop by drop just at the position of the roots. So, it is called drip system. Water is not wasted at all. It is the best technique for watering fruit plants, gardens and trees.
Lakhmir Singh Science Class 8 Chapter 1 Questions Based on High Order Thinking Skills (HOTS)
Question 91.
Arrange the following practices in the correct order as they appear in the sugarcane crop production:
Sending crop to sugar factory; Irrigation; Harvesting; Sowing; Preparation of soil; Ploughing the field; Manuring.
Answer:
The correct order is : Ploughing the field ; Preparation of soil, Sowing; Manuring; Irrigation; Harvesting; Sending crop to sugar factory
Question 92.
Match items in column A with those in column B:
Column A
(i) Kharif crops
(ii) Rabi crops
(iii) Chemical fertilizers
(iv) Organic manure
Column B
(a) Food for cattle
(b) Urea and super Phosphate
(c) Animal excreta, cow-dung, and plant waste
(d) Wheat, gram, pea
(e) Paddy and maize
Answer:
(i) e
(ii) d
(iii) b
(iv) c
Question 93.
Name two crops which are cultivated:
(a) by sowing seeds directly into fields.
(b) by transplanting.
Answer:
(a) Crops wheat and gram can be cultivated by sowing seeds directly into fields.
(b) Paddy and tomatoes can be cultivated by transplanting.
Question 94.
Farmers in Northern India grow legumes as fodder in one season and wheat in the next season.
(a) What is this practice known as ?
(b) How does this practice help in the replenishment of soil?
Answer:
(a) Crop rotation
(b) The nitrogen-fixing bacteria present in root nodules of leguminous plants is rhizobium bacteria. Rotation of crops (leguminous and non-leguminous crops) in the same field replenishes the soil with nitrogen naturally and increases the soil fertility.
Question 95
A student lists the following agricultural practices for crop production:
Irrigation; Removal of weeds; Preparation of soil; Storage of food grains; Sowing; Adding manure and fertilizers
Which agricultural practice is missing from the above list?
Answer:
Harvesting is missing from the above list.


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k c nag miscellaneous question

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