NEET BIOLOGY

Detailed explanation-1: -Examples of discontinuous variation include a person’s blood group or the color of a species of bird. These variations can exist for two major reasons. They could be purely random genetic changes, or they can be traits that have been influenced and selected by the environment.

Detailed explanation-2: -Discontinuous variations are decided by a single gene or a small number of genes. The phenotypic appearances of them are generally not affected due to environmental factors. Discontinuous variation does not show a normal distribution.

Detailed explanation-3: -Genetic basis of discontinuous variation At the genetic level: Different genes have different effects on the phenotype. Different alleles at a single gene locus have a large effect on the phenotype. Remember diploid organisms will inherit two alleles of each gene, these alleles can be the same or different.

Detailed explanation-4: -These characteristics are usually controlled by alleles of one gene or a small number of genes, and are not strongly influenced by the environment. An example of discontinuous variation is blood type in humans. There are four categories (A, B, AB or O), and humans can only belong to one of these categories.

Detailed explanation-5: -So, the correct answer is ‘Mutations’