What is the potential consequence of nondisjunction during meiosis?

• A. Aneuploidy
• B. Increased fertility
• C. Decreased mutation rates
• D. Enhanced genetic diversity

Answer: (A)

Nondisjunction during meiosis is the failure of homologous chromosomes or sister chromatids to separate properly during cell division. This results in gametes with an abnormal number of chromosomes. When these gametes fuse during fertilization, it can lead to aneuploidy, which is a condition characterized by an abnormal number of chromosomes in the resulting offspring. For instance, if a gamete with an extra chromosome participates in fertilization, it can lead to disorders such as Down syndrome, which is caused by the presence of an extra copy of chromosome 21.

Aneuploidy can have significant effects on development and health, highlighting the importance of correct chromosomal segregation. The other options presented refer to different genetic phenomena, such as increased fertility or enhanced genetic diversity, which are not direct consequences of nondisjunction. Additionally, decreased mutation rates are unrelated to the process of nondisjunction and its outcomes. Therefore, the correct answer reflects the direct consequence of nondisjunction.