Crop Production and Management - Exemplar Solutions 3

CBSE Class 08 Science
NCERT Exemplar Solutions
CHAPTER - 1
Crop Production and Management
SHORT ANSWER QUESTIONS
17. Beera, wants to practice crop rotation in his field. Suggest a Rabi crop and a Kharif crop which will replenish his field with nitrogen. Which crop replenishes nitrogen and why?
Ans. Kharif: Rice or Soyabean, Rabi: Pea or Wheat.
Pea/Soyabean are legumes that will fix nitrogen as the roots of them are habitat for Rhizobium bacteria which helps in nitrogen fixation.
18. Match the agricultural implements given in Column A with their use given in Column B.
Column A
Column B
(i) Sickle
(a) Ploughing
(ii) Hoe
(b) Sowing
(iii) Seed Drill
(c) Harvesting
(iv) Sprinkler
(d) Irrigation
Ans. (i)-c; (ii)-a; (iii)-b; (iv)-d
19. What are organic foods?
Ans. Organic foods refers to those food stuffs that are produced without the use of any synthetic method including use of pesticides,fertilisers, sewage sludge .
organic foods are also usually not processed using irradiation, industrial solvents or synthetic food additives.
Organic animal food products like meat, poultry, eggs, and dairy products are obtained from animals without the use of any antibiotics or growth hormones.
20. From the word puzzle given as Fig. 1.1 find atleast eight words which are ‘farmer’s friends.’ Classify them into living and non-living.
Ans.
Living: Seed, Earthworm, Rhizobium, Microbes, Ox
Non-living: Plough, Urea, NPK, Manure, Hoe
21. (a) Name the tool used with a tractor for sowing seeds in a field.
(b) What are the advantages of using this tool?
Ans. (a) Seed drill.
(b) The advantages are, can be pulled across the field using bullocks or a tractor.xz Precise planting, improves ratio of crop yield.
(i) Seeds are sown at a uniform distance and depth to avoid overcrowding.
(ii) It ensures that after sowing, seeds are covered by soil which prevent them from being eaten by birds.
(iii) It saves time and labour.
22. (a) Name the practice followed for large scale rearing of farm animals.
(b) What facilities are provided to farm animals?
Ans. (a) Animal husbandry.
  • (b) Animals are provided
  • proper food
  • shelter
  • medical facilities
  • like companions
23. Classify the following crops into Khariff and Rabi crops and write in the tabular column given below:
Maize, paddy, mustard, pea, gram, wheat, groundnut, cotton.
Ans.
Kharif(sown in autumn)
Rabi(sown in winter)
Paddy
Mustard
Maize
Gram
Groundnut
Pea
Cotton
Wheat