AP BIOLOGY

Detailed explanation-1: -Genetic variation is the variation in the DNA sequences between individuals. Genes are specific sequences of DNA that code for a trait, and alleles are different versions of a gene. Alleles lead to genotypic variation, which is the variation in genotypes between individuals.

Detailed explanation-2: -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-3: -Genotype generally remains constant from one environment to another, although occasional spontaneous mutations may occur which cause it to change. However, when the same genotype is subjected to different environments, it can produce a wide range of phenotypes.

Detailed explanation-4: -Answer and Explanation: The correct answer to this question is B. They always cause a change to an organism’s genotype. Regardless of the cause of the change, a DNA sequence is always altered when it mutates.

Detailed explanation-5: -The genetic diversity has three different sources: mutation, recombination and immigration of genes. Mutation is the driving force of genetic variation and evolution.