AP BIOLOGY

Detailed explanation-1: -point mutation, change within a gene in which one base pair in the DNA sequence is altered. Point mutations are frequently the result of mistakes made during DNA replication, although modification of DNA, such as through exposure to X-rays or to ultraviolet radiation, also can induce point mutations.

Detailed explanation-2: -Definition. A point mutation occurs in a genome when a single base pair is added, deleted or changed. While most point mutations are benign, they can also have various functional consequences, including changes in gene expression or alterations in encoded proteins.

Detailed explanation-3: -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-4: -Final answer: Point mutation involves a change in a single base pair.

Detailed explanation-5: -Deletions A deletion, resulting in a frameshift, results when one or more base pairs are lost from the DNA (see Figure above).