What is Nondisjunction in meiosis?

What is Nondisjunction in meiosis?

• A. Separation of sister chromatids
• B. Failure of homologous chromosomes to separate
• C. Production of zygotes
• D. Formation of haploid cells

Answer: (B)

Nondisjunction in meiosis refers to the failure of homologous chromosomes to separate properly during the cell division process. This occurrence can take place during either meiosis I or meiosis II. When homologous chromosomes do not segregate as they should, one cell may receive both copies of a chromosome while another receives none. This can result in gametes that have an abnormal number of chromosomes, which can lead to genetic disorders in offspring if these gametes participate in fertilization. In the context of meiosis, sister chromatids separate normally during either of the meiotic divisions; therefore, focusing on the failure of homologous chromosomes provides a clear understanding of nondisjunction. The production of zygotes and the formation of haploid cells pertain to the overall outcomes of meiosis but do not directly describe the specific event of nondisjunction.

Nondisjunction in meiosis refers to the failure of homologous chromosomes to separate properly during the cell division process. This occurrence can take place during either meiosis I or meiosis II. When homologous chromosomes do not segregate as they should, one cell may receive both copies of a chromosome while another receives none. This can result in gametes that have an abnormal number of chromosomes, which can lead to genetic disorders in offspring if these gametes participate in fertilization.

In the context of meiosis, sister chromatids separate normally during either of the meiotic divisions; therefore, focusing on the failure of homologous chromosomes provides a clear understanding of nondisjunction. The production of zygotes and the formation of haploid cells pertain to the overall outcomes of meiosis but do not directly describe the specific event of nondisjunction.