Final answer:
An individual with one normal chromosome and one with an inverted segment is called an inversion heterozygote. This condition can lead to the formation of aneuploid gametes during meiosis.
Step-by-step explanation:
An individual that carries one copy of a normal chromosome and one copy that contains an inverted segment is described by the term inversion heterozygote. A chromosome inversion occurs when a section of a chromosome breaks off, undergoes a 180° rotation, and is reinserted into the chromosome. If during meiosis, one homologous chromosome has an inversion and the other does not, the chromosomal structure demands that one chromosome forms a loop during pairing to maintain proper alignment of genes. This individual can still be euploid, meaning they have the correct number of chromosomes for their species, but the structural modification of the chromosome can lead to issues during meiosis, causing aneuploid gametes.