NEET BIOLOGY

Detailed explanation-1: -Genetic variations can arise from gene variants (also called mutations) or from a normal process in which genetic material is rearranged as a cell is getting ready to divide (known as genetic recombination). Genetic variations that alter gene activity or protein function can introduce different traits in an organism.

Detailed explanation-2: -The mutation of genes is an important source of genetic variation within a population. Mutations can be random (for example, when replicating cells make an error while copying DNA), or happen as a result of exposure to something in the environment, like harmful chemicals or radiation.

Detailed explanation-3: -Mutation (which can produce whole new alleles in a population), random mating, random fertilisation, and linkage among homologous chromosomes during meiosis can contribute to genetic variation.

Detailed explanation-4: -Major causes of variation include mutations, gene flow, and sexual reproduction. DNA mutation causes genetic variation by altering the genes of individuals in a population. Gene flow leads to genetic variation as new individuals with different gene combinations migrate into a population.