AP BIOLOGY

Detailed explanation-1: -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-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 Point Mutations. We are going to focus on the following point mutations: frameshift, silent, nonsense, and missense. Let’s start with a frameshift mutation, where there’s an insertion or deletion of one or more bases.

Detailed explanation-4: -Listen to pronunciation. (poynt myoo-TAY-shun) A genetic alteration caused by the substitution of a single nucleotide for another nucleotide.

Detailed explanation-5: -Single base substitutions are called point mutations, recall the point mutation Glu—–> Val which causes sickle-cell disease.