AIIMS 2019 Biology Hybrid Vigour MCQ Question

Hybrid vigour, also known as heterosis, refers to the enhanced biological performance observed in hybrid offspring compared to their parents, often due to increased heterozygosity. Option (A) is correct because heterosis specifically describes the phenomenon where hybrid individuals exhibit superior traits, such as growth rate or fertility, resulting from the combination of diverse genetic backgrounds.

In contrast, option (B) homozygosity refers to having identical alleles for a particular gene, which can lead to inbreeding depression rather than vigour. Option (C) heterozygosity indicates the presence of different alleles at a gene locus, but it does not specifically denote the performance benefits seen in hybrids. Option (D) homosis is not a recognized term in genetics related to hybrid vigour.