NEET BIOLOGY

Detailed explanation-1: -Definition. A polygenic trait is a characteristic, such as height or skin color, that is influenced by two or more genes. Because multiple genes are involved, polygenic traits do not follow the patterns of Mendelian inheritance . Many polygenic traits are also influenced by the environment and are called multifactorial.

Detailed explanation-2: -Polygenic inheritance is controlled by two types of alleles or genes, namely: Contributing alleles: Alleles that contribute to continuous variation are referred to as contributing alleles. Non-contributing alleles: Alleles that do not contribute to continuous variation are referred to as non-contributing alleles.

Detailed explanation-3: -In polygenic inheritance, a particular trait is controlled by 3 different genes. The given problem is of polygenic inheritance. In this, phenotypic ratio is 1:6:15:20:15:6:1 instead of 27:9:9:9:3:3:3:1 in F2 generation. In the given example, the genotype of parents is AaBbCc and AaBbCc.

Detailed explanation-4: -Polygenic inheritance refers to the inheritance of a trait governed by more than one genes. Generally, three or more genes govern the inheritance of polygenic traits.

Detailed explanation-5: -So, the correct option is ‘Polygenic trait is controlled by multiple alleles’.