During meiosis I, what happens to homologous chromosomes?

• A. They are duplicated.
• B. They separate, resulting in two haploid cells.
• C. They align at metaphase plate.
• D. They do not separate.

Answer: (B)

Meiosis I is the reduction division, so homologous chromosomes are separated into opposite daughter cells. After DNA replication in interphase, each chromosome consists of two sister chromatids. During anaphase I, the paired homologs are pulled apart, and each daughter cell ends up with one chromosome from each homologous pair. This halves the chromosome number, producing two haploid cells. The sister chromatids stay together and are only separated later in meiosis II. Duplication occurs before meiosis I (in S phase), and alignment at the metaphase plate happens as a step within meiosis I, not the final outcome.