During Metaphase I, what happens to homologous chromosome pairs?

During Metaphase I, what happens to homologous chromosome pairs?

• A. They align at the equatorial plate
• B. They duplicate
• C. They migrate to the poles
• D. They condense

Answer: (A)

In metaphase I, homologous chromosome pairs align at the cell’s equatorial plate. Each pair, consisting of two sister chromatids, has kinetochores attached to spindle fibers from opposite poles, preparing for their separation in the next stage. Duplication has already occurred in S phase earlier, chromosome condensation happened in prophase I, and migration to the poles happens later in anaphase I. Aligning at the equator is the defining arrangement of metaphase I.

In metaphase I, homologous chromosome pairs align at the cell’s equatorial plate. Each pair, consisting of two sister chromatids, has kinetochores attached to spindle fibers from opposite poles, preparing for their separation in the next stage. Duplication has already occurred in S phase earlier, chromosome condensation happened in prophase I, and migration to the poles happens later in anaphase I. Aligning at the equator is the defining arrangement of metaphase I.