AP BIOLOGY

Detailed explanation-1: -Substitution, as related to genomics, is a type of mutation in which one nucleotide is replaced by a different nucleotide.

Detailed explanation-2: -A substitution is a mutation that exchanges one base for another (i.e., a change in a single “chemical letter” such as switching an A to a G). Such a substitution could: change a codon to one that encodes a different amino acid and cause a small change in the protein produced.

Detailed explanation-3: -Types of Substitution Mutations Within the four nucleotides, there are two types: the purines and pyrimidines. Adenine (A) and guanine (G) are both purines, while cytosine (C) and thymine (T) are pyrimidines. If a purine changes to a purine, the substitution mutation is considered a transition.

Detailed explanation-4: -Substitution mutation is sometimes referred to as point mutation. However, point mutation is defined particularly as a type of mutation involving a change of only one nucleotide. See also: transversion. transition.

Detailed explanation-5: -Mutations can be of many types, such as substitution, deletion, insertion, and translocation.