NCEA Level 2 Biology Genetics Practice Exam

The term that best describes an organism that has variation due to chromosomal alterations is "variant." In genetics, a variant is typically used to refer to any change in the DNA sequence that can give rise to different traits among individuals. Chromosomal alterations, which include changes such as duplications, deletions, inversions, or translocations of chromosome segments, can lead to the production of new alleles or different combinations of genetic material. This genetic variability can result in observable differences in phenotype among organisms, making "variant" the most appropriate descriptor.

Other terms, such as "clonal," refer to organisms that are genetically identical due to asexual reproduction and do not exhibit variation due to chromosomal changes. "Modified" generally implies changes to existing structures rather than the emergence of new genetic variations, and "recessive" specifically relates to alleles that do not manifest in the phenotype when a dominant allele is present. Therefore, "variant" is the most suitable choice for describing organisms affected by chromosomal alterations leading to variation.