During metaphase I of meiosis, which of the following events occurs?

• A. Sister chromatids separate and move to opposite poles.
• B. DNA replication takes place.
• C. The nuclear envelope reforms around separated chromosomes.
• D. Homologous chromosomes align as pairs along the metaphase plate.

Answer: (D)

Verified step by step guidance

1. Understand the context of meiosis: Meiosis is a type of cell division that reduces the chromosome number by half, creating four haploid cells. It consists of two stages: meiosis I and meiosis II. Metaphase I occurs during meiosis I.
2. Recall the key event of metaphase I: During metaphase I, homologous chromosomes (pairs of chromosomes, one from each parent) align along the metaphase plate. This alignment is crucial for the subsequent separation of homologous chromosomes during anaphase I.
3. Differentiate homologous chromosomes from sister chromatids: Homologous chromosomes are pairs of chromosomes that are similar but not identical, while sister chromatids are identical copies of a single chromosome. In metaphase I, homologous chromosomes align, not sister chromatids.
4. Eliminate incorrect options: Sister chromatids separate during anaphase II, not metaphase I. DNA replication occurs during the S phase of interphase, not during meiosis. The nuclear envelope reforms during telophase, not metaphase I.
5. Conclude the correct event: The alignment of homologous chromosomes as pairs along the metaphase plate is the defining feature of metaphase I in meiosis.