Last updated on August 30th, 2023 at 01:55 am
Lakhmir Singh Science Class 8 Chapter 1 Solutions
Lakhmir Singh Science Class 8 Chapter 1 Very Short Answer Type Questions
1. Which agricultural practice is carried out with the help of a sickle ?
Agricultural practice carried out with the help of a sickle: Harvesting or cutting crops.
2. What name is given to the cutting and gathering of a food crop like wheat or paddy ?
Name for cutting and gathering food crop like wheat or paddy: Harvesting.
3. Name the tool (or implement) used in the traditional harvesting of crops.
Tool used in traditional harvesting of crops: Sickle.
4. Name the process of beating out the grains from harvested crop.
Process of beating out grains from harvested crop: Threshing.
5. Name the machine used in recovering the grain from already cut crop.
Machine used in recovering grain from already cut crop: Combine harvester.
6. Name the machine which does the cutting of standing crops and recovers the grain too.
Machine that cuts standing crops and recovers grain: Combine harvester.
7. Name the process in which grains are separated from chaff and hay with the help of wind.
Process of separating grains from chaff and hay with wind: Winnowing.
8. Name three food materials obtained from animals.
Three food materials obtained from animals: Meat, Milk, Eggs.
9. Name two domestic animals which are used to obtain milk.
Two domestic animals used to obtain milk: Cow, Goat.
10. Name one meat yielding animal and one egg yielding animal.
Meat yielding animal: Chicken (Poultry), Egg yielding animal:** Hen.
11. Name an animal food obtained from insects.
Animal food obtained from insects: Honey
12. What name is given to that branch of agriculture which deals with feeding, shelter, health and breeding of domestic animals ?
Branch of agriculture dealing with domestic animals: Animal Husbandry.
13. Name the major food nutrient provided by fish.
Major food nutrient provided by fish: Protein.
14. Name the vitamin/vitamins present in cod liver oil.
Vitamin present in cod liver oil: Vitamin A (and D).
15. Name one Government Agency which is involved in procuring food grains (like wheat and rice) from farmers and storing them properly.
Government Agency involved in procuring food grains: Food Corporation of India (FCI).
16. What type of organisms grow on stored food grains having higher moisture content ?
Organisms growing on stored food grains with higher moisture content: Fungi.
17. Which crop is generally grown between two cereal crops in crop rotation to restore the fertility of soil ?
Crop grown between two cereal crops to restore soil fertility: Leguminous crop (e.g., pulses).
18. State one advantage of growing a leguminous crop between two cereal crops.
Advantage of growing leguminous crop between two cereals: Leguminous crops fix nitrogen in the soil, enhancing its fertility.
19. Name the nitrogen-fixing bacteria present in root nodules of leguminous plants.
Nitrogen-fixing bacteria in root nodules of leguminous plants: Rhizobium.
20. Which agricultural practice comes first : harvesting or weeding ?
Agricultural practice that comes first: Harvesting or weeding: Weeding.
21. Which is the first step in the cultivation of a crop ?
First step in the cultivation of a crop: Plowing or tilling the soil.
22. For what purpose is a hoe used ?
Purpose of a hoe: To loosen and cultivate the soil, remove weeds, and create furrows for planting.
23. Name the implement used in sowing.
Implement used in sowing: Seed drill.
24. Name the practice used for cultivating paddy.
Paddy cultivation is commonly done using the practice of “transplanting,” where young paddy seedlings are grown in a nursery and then transplanted to the main field.
25. Name the two types of substances which are added to the fields by the farmers to maintain the fertility of soil.
Organic matter (compost, manure) and fertilizers.
26. Some grass is growing in a wheat field. What will it be known as ?
Grass growing in a wheat field: Weed.
27. Name one crop which can tolerate standing water (water-logging) in the field and one which cannot.
Crop tolerating standing water (water-logging): Rice (paddy). Crop not tolerating water-logging: Wheat.
28. Which is the best time for the removal of weeds ?
Best time for weed removal: Early stages of crop growth.
29. Name two methods of irrigation which conserve water.
Drip irrigation and sprinkler irrigation.
30. Fill in the following blanks with suitable words :
(a) The same kind of plants grown and cultivated on a large scale at a place is called ………….[crop]
(b) The first step before growing crops is …………….of soil.[plowing/tilling]
(c) For growing a crop, sufficient sunlight, ……….., and ………… from the soil are essential.[water/nutrients]
(d) Damaged seeds would …………. on top of water.[float]
(e) Crop rotation helps in the replenishment of soil with …………..[nutrients]
(f) The supply of water to crops at different intervals is called …………..[irrigation]
(g) The unwanted plants present in a crop field are called ……………[weeds]
(h) Dried…………..leaves are used for storing food grains at home.[neem ]
(i) Many people living in the …………….areas consume fish as a major part of their diet.[coastal/maritime]
Lakhmir Singh Science Class 8 Chapter 1 Short Answer Type Questions
31.
(a) Why is it is necessary to dry the harvested food grains before storage ?
Drying harvested food grains is necessary to reduce their moisture content. High moisture can lead to mold growth, spoilage, and insect infestation during storage.
(b) What are the two ways in which farmers store food grains ?
Farmers store food grains in bags or sacks and in storage structures like granaries or silos.
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 ?
(a) Drip system is more suitable for uneven land.
(b) Sprinkler system is more suitable for sandy soil.
(c) Drip system is more suitable for watering fruit plants.
(d) Drip system is more suitable where availability of water is poor.
33.
(a) What are weeds ? Name any one weed found in a crop field.
Weeds are unwanted plants that grow along with crops. One example is Amaranthus (Amaranth).
(b) How do weeds affect the growth of crops ?
Weeds compete with crops for nutrients, water, and light, thereby reducing crop yield.
34. Explain how, the irrigation requirements depend on the nature of the crop.
The irrigation requirements of a crop depend on its water needs, growth stage, climate, and soil type. Some crops require more water during germination and flowering, while others need less water during those stages.
35. Explain how, the irrigation requirements of a crop depend on the nature of soil in which the crop is grown.
The irrigation requirements of a crop depend on soil type. Sandy soil drains quickly and may need more frequent irrigation, while clay soil retains water and might require less frequent irrigation.
36. Describe the sprinkler system of irrigation. State its advantages.
In this system, water is sprayed over the crop in the form of droplets. Advantages include uniform water distribution, reduced water wastage, and suitability for various crop types.
37. Explain the drip system of irrigation. State two advantages of the drip system of irrigation.
In this system, water is delivered directly to the root zone of plants through pipes and tubes. Advantages include water efficiency, reduced weed growth, and minimal water wastage.
38. How do the irrigation requirements of a wheat crop differ from that of a paddy crop ?
The irrigation requirements of a wheat crop are generally lower than those of a paddy crop. Wheat requires less water and can be grown with relatively less irrigation.
39. Explain why, the frequency of irrigation of crops is higher in summer season.
The frequency of irrigation is higher in the summer season due to higher evaporation rates and increased water requirement by plants.
40. How are weeds removed from the crop fields ? Name one implement used for weeding.
Weeds are removed from crop fields through a process called weeding. One implement used for weeding is a hoe.
41. If wheat is sown in the kharif season, what would happen ? Discuss.
If wheat is sown in the kharif season, it would face unfavorable conditions like excess rain and high humidity, leading to poor germination and growth.
42. Which of the following are kharif crops and which are rabi crops ?
Wheat, Paddy, Gram, Maize, Mustard, Cotton, Soyabean, Linseed, Peas, Groundnut
Kharif crops: Paddy, Maize, Cotton, Groundnut, Soyabean.
Rabi crops: Wheat, Gram, Mustard, Peas, Linseed.
43. What is a crop ? Give two examples of crops.
A crop is a cultivated plant that is grown and harvested for food, fiber, or other valuable products. Examples: Wheat, Rice.
44. What are the two types of crops based on seasons ? Give one example of each type.
Two types of crops based on seasons: Kharif (monsoon season) and Rabi (winter season). Example of Kharif crop: Paddy; Example of Rabi crop: Wheat.
45. Name the various agricultural practices in the right sequence in which they are undertaken by the farmers.
Various agricultural practices in sequence: Plowing/Tilling → Sowing → Irrigation → Weeding → Harvesting.
46. Describe briefly, how soil is prepared for sowing the seeds.
Soil is prepared for sowing by plowing or tilling, which involves turning and loosening the soil to create a suitable seedbed.
47. Why do farmers carry out levelling of the ploughed fields ?
Farmers carry out leveling of plowed fields to ensure uniform water distribution during irrigation and prevent waterlogging in low-lying areas.
48. What are the advantages of sowing seeds with a seed drill ?
Advantages of sowing seeds with a seed drill include accurate seed placement, uniform spacing, and efficient use of seeds.
49. Explain why, the seeds should be sown at right spacings.
Seeds should be sown at right spacings to avoid overcrowding, which can lead to competition for resources and reduced crop yield.
50. What is ploughing (or tilling) ? Name any two implements used for tilling the fields.
Ploughing is the process of turning and loosening the soil using a plough or disc harrow.
51. State two beneficial effects of ploughing the fields (or loosening and turning the soil).
Beneficial effects of ploughing include aeration of soil, incorporation of organic matter, and disruption of weed growth.
52.
(a) State the function of Food Corporation of India.
FCI procures, stores, and distributes food grains to maintain food security in the country.
(b) What is done to protect the grains stored in gunny bags in big godowns from damage ?
Grains stored in gunny bags are protected from damage by fumigation or use of pesticides.
53. Define manure. What are the advantages of manure ?
Manure is organic matter obtained from decomposed plant and animal waste. Advantages include improved soil structure, nutrient supply, and soil fertility.
54. What is a fertiliser ? Name any two fertilisers. State two harmful effects caused by the excessive use of fertilisers.
Fertilizers are synthetic substances containing essential nutrients for plant growth. Examples: Nitrogenous fertilizers, Phosphatic fertilizers. Harmful effects of excessive use include water pollution and soil degradation.
55. Explain how, soil gets affected by the repeated growing of crops in the same fields. How does use of fertilisers help the farmers ?
Repeatedly growing crops in the same fields depletes soil nutrients. Fertilizer use helps replenish nutrients, enhancing crop productivity.
56. What is weeding ? Why is weeding necessary ?
Weeding is the process of removing unwanted plants (weeds) from crop fields. Weeding is necessary to prevent competition for resources and to ensure healthy crop growth.
57. What are weedicides ? Name one weedicide.
Weedicides are chemicals used to control or kill weeds. Example: Glyphosate.
58. What precaution should be taken while spraying weedicides ? Why ?
Precaution while spraying weedicides: Avoid spraying on windy days to prevent drift and unintended damage to non-target plants.
59. Give any four differences between manures and fertilisers.
Manures are organic, natural substances; Fertilizers are synthetic.
Manures release nutrients slowly; fertilizers provide nutrients rapidly.
Manures improve soil structure; fertilizers may not.
Manures add organic matter to soil; fertilizers do not contribute to soil organic matter.
