AIIMS 2012
- Exam
- AIIMS
- Year
- 2012
- Subject
- Zoology
- Chapter
- Strategies for Enhancement in Food Production
AIIMS 2012 · Zoology · Strategies for Enhancement in Food Production
Assertion : Inbreeding increases homozygosity, thus exposes harmful...
Assertion : Inbreeding increases homozygosity, thus exposes harmful recessive genes, which are eliminated by selection.Reason : Continued inbreeding reduces fertility and productivity.
Options
- AIf both assertion and reason are true and reason is the correct explanation of assertion
- BIf both assertion and reason are true but reason is not the correct explanation of assertion
- CIf assertion is true but reason is false
- DIf both assertion and reason are false
Correct answer
B. If both assertion and reason are true but reason is not the correct explanation of assertion
Step-by-step solution
When the offsprings are produced by self fertilization or breeding between closely related parents it is called inbreeding. Inbreeding results in increase in homozygosity. The most revealing impact of inbreeding is the loss of vigour and physiological efficiency of the organisms characterized by reduction in size. A number of lethal and defective characters appear in the population which has undergone inbreeding (selfing). This loss of fitness in the progenies or decline in character expression with decreased heterozygosity arising from self mating is known as inbreeding depression or inbreeding decline. Continued inbreeding reduces fertility and even productivity. But the inbreeding progeny with lethal and harmful recessive genes being homozygous express these traits which otherwise remain hidden in heterozygous individuals. Natural selection works upon these individuals and eliminate them. Gradually, such genes get eliminated from the population.