What term describes a segment of DNA that is reversed in order?

The correct term for a segment of DNA that is reversed in order is "inversion." An inversion occurs when a segment of the chromosome is flipped in orientation, so that the order of the nucleotides is reversed. This can potentially affect the expression of genes located near the breakpoints of the inverted segment, as the orientation of regulatory elements may change.

Understanding inversion is crucial in genetics, as it can play a significant role in evolution and can lead to various genetic disorders if it disrupts important genes. This structural alteration can occur naturally or be induced by mutagens and has implications in areas such as breeding and conservation biology.

In contrast, duplication involves the replication of a segment of DNA, leading to an extra copy of that segment. Translocation refers to the movement of a segment from one location to another, either within the same chromosome or between different chromosomes. Mutation is a broader term that encompasses any change in the DNA sequence, not limited to reversals or specific types of rearrangements.