Advertisement

CBSE Class 12 Biology NCERT Exemplar Solutions: Strategies for Enhancement in Food Production

Students who are having trouble finding the right and simple answers for the Class 12 Biology NCERT Exemplar problems, can refer the answers given by experts at jagranjosh.com.

In this article we are providing the NCERT Exemplar solutions for Class 12 Biology chapter – Strategies for Enhancement in Food Production. All these model solutions have been prepared in the simplest way so that students can easily understand the concept and theories involved in each solution. NCERT Exemplar solutions provided here will make learning easier and simpler than ever before.

All the class 12 Biology NCERT Exemplar solutions have been collated in PDF format which students may easily download totally free. 

Few problems along with their solutions from this chapter are given follows:

Q. Inbreeding is carried out in animal husbandry because it

(a) increases vigour         (b) improves the breed

(c) increases heterozygosity       (d) increases homozygosity

Ans. (d) increases homozygosity              

Inbreeding increases homozygosity, i.e., state of possessing two identical alleles, one inherited from each parent. It is necessary if we want to evolve a pure line in any animal.

Inbreeding exposes harmful recessive genes that are eliminated by selection. It also helps in accumulation of superior genes and elimination of less desirable genes.

Q. The biggest constraint of plant breeding is

(a)    Availability of desirable gene in the crop and its wild relatives

(b)   Infrastructure

(c)    trained manpower

(d)   transfer of genes from unrelated sources

Ans. (a) availability of desirable gene in the crop and its wild relatives    

Breeding (conventional) is often constrained by the availability of limited number of disease resistant genes that are present and identified in various crop varieties or wild relatives.

Q. How is a somatic hybrid different from a hybrid?

Ans. Somatic hybrids are obtained by uniting protoplasts from two different varieties of plants and then further cultured to form a novel plant. Compatibility between two plants is not a limitation. Any two protoplasts can be united whereas hybrids are obtained by crossing two selected parent plants of opposite sex. Many times compatibility is a limitation for breeding.

Q. “Give me a living cell of any plant and I will give you a thousand plants of the same type.” Is this only a slogan or is it scientifically possible? Write your comments and justify them.

Ans. It is scientifically possible to grow thousand plants from a living cell of any plant and this process is called micropropagation. The property of plant cells that helped them to grow into a new plant is totipotency. Micropropagation is the use of plant cell culture to regenerate large number of plants. This results in genetically identical plants and is also called clonal propagation. Hence, the desirable characters are kept constant for many generations.

Micropropagation is widely used in forestry and in floriculture. Plants can be obtained throughout the year under controlled conditions.

CBSE Class 12 Biology Syllabus 2018 - 2019

Find below the links to download Class 12 Biology NCERT Exemplar Solutions for chapter 9 - Strategies for Enhancement in Food Production:

Questions

Link to Download PDF

Multiple Choice Questions

Download

Very Short answer type questions

Download