AP BIOLOGY

Detailed explanation-1: -Answer: B. A change in the nucleotide sequence. Mutation can be described as permanent change in the genetic material of living organisms (that is DNA, deoxyribonucleic acid). In other words, it depicts change in the sequence of nucleotide within gene (a segment of DNA that codes for particular protein).

Detailed explanation-2: -A mutation (Section 14.1) is a change in the nucleotide sequence of a short region of a genome (Figure 14.1A). Many mutations are point mutations that replace one nucleotide with another; others involve insertion or deletion of one or a few nucleotides.

Detailed explanation-3: -A frameshift mutation is a genetic mutation caused by a deletion or insertion in a DNA sequence that shifts the way the sequence is read. A DNA sequence is a chain of many smaller molecules called nucleotides.

Detailed explanation-4: -A gene variant is a permanent change in the DNA sequence that makes up a gene. This type of genetic change used to be known as a gene mutation, but because changes in DNA do not always cause disease, it is thought that gene variant is a more accurate term.

Detailed explanation-5: -A mutation is a change in a genetic sequence. Mutations include changes as small as the substitution of a single DNA building block, or nucleotide base, with another nucleotide base.