Extra Questions for Class 12 Biology Chapter 9 Strategies for Enhancement in Food Production
Q.1. A herd of cattle is showing reduced fertility and productivity. Provide one reason and one suggestion to overcome this problem.
Ans. Inbreeding depression or continuous inbreeding may be the reason of reduced fertility and productivity. To overcome this, the cattle should be mated with unrelated superior cattle of the same breed.
Q.2. Write the importance of MOET.
Ans. MOET is used to increase the herd size in a short time. It also improves the chances of production of hybrids.
Q.3. Which of the following is the semi-dwarf wheat that is high yielding and disease resistant?
Pusa Shubra, Kalyan sona, Ratna
Ans. Kalyan sona
Q.4. Write the name of the following:
(a) The most common species of bees suitable for apiculture.
(b) An improved breed of chicken.
Ans. (a) Apis indica/Apis mellifera/Apis dorsata
(b) Leghorn/Rhode island red/Minorca.
Q.5. Mention the strategy used to increase homozygosity in cattle for desired traits.
Ans. Inbreeding
Q.6. Why are apical and axillary meristems used for tissue culture?
Ans. Because these are free from virus.
Q.7. Write an alternate source of protein for animal and human nutrition.
Ans. Single cell protein/Spirulina
Q.8. Name the following:
(a) The semi-dwarf variety of wheat which is high-yielding and disease-resistant.
(b) Any one inter-specific hybrid mammal.
Ans. (a) Kalyan Sona/Sonalika
(b) Mule/Hinny/Liger/Tigon
Q.9. Name any two diseases the ‘Himgiri’ variety of wheat is resistant to.
Ans. Leaf and stripe rust; Hill bunt
Q.10. Identify two correct statements from the following:
(i) Apiculture means apical meristem culture.
(ii) Spinach is iron-enriched.
(iii) Green revolution has resulted in improved pulse-yield.
(iv) Aphids cannot infest rapeseed mustard.
Ans. (ii) and (iv) are correct.
Q.11. Write the names of two semi-dwarf and high yielding rice varieties developed in India after 1966.
Ans. Jaya, Ratna.
Q.12. What can be used as the reference material for comparison of any new improved variety?
Ans. The best available local cultivar.
Q.13. Why is the South Indian sugarcane preferred by agriculturalists?
Ans. South Indian sugarcane has thicker stem and higher sugar content.
Q.14. Name the technology which in addition to tissue culture techniques play a pivotal role in enhancing food production.
Ans. Somatic hybridisation, Multiple Ovulation Embryo Transfer Technology
Q.15. Select two disease resistant crop varieties from the list of crop varieties given below:
Himgiri, Pusa Gaurav, Pusa Komal, Pusa A-4
Ans. Himgiri; Pusa Komal
Q.16. What is meant by ‘hidden hunger’?
Ans. Consumption of food deficient in nutrients particularly, micronutrients, proteins and vitamins is called hidden hunger.
Q.17. Why is mutation breeding necessary for producing disease resistance varieties?
Ans. Because there is limited availability of disease resistance genes in the crop plants and their wild relatives.
Q.18. State any one significance of interspecific hybridisation in plants.
Ans. It is important for breeding disease-resistant plant varieties.