In which phase do chromosomes align at the center of the cell along the metaphase plate?

In which phase do chromosomes align at the center of the cell along the metaphase plate?

• A. Prophase
• B. Metaphase
• C. Anaphase
• D. Telophase

Answer: (B)

The event being tested is the alignment of chromosomes at the cell’s equator during mitosis. This happens in metaphase: the spindle apparatus is fully formed, kinetochores attach to microtubules, and chromosomes line up along the metaphase plate, a plane midway between the two poles. This precise alignment sets the stage for equal sister chromatid separation in the next phase. In prophase, chromosomes condense and the nuclear envelope breaks down but don’t align at the center; in anaphase, sister chromatids are pulled apart toward opposite poles; in telophase, they arrive at the poles and the chromosome de-condense as the nucleus reforms.

The event being tested is the alignment of chromosomes at the cell’s equator during mitosis. This happens in metaphase: the spindle apparatus is fully formed, kinetochores attach to microtubules, and chromosomes line up along the metaphase plate, a plane midway between the two poles. This precise alignment sets the stage for equal sister chromatid separation in the next phase. In prophase, chromosomes condense and the nuclear envelope breaks down but don’t align at the center; in anaphase, sister chromatids are pulled apart toward opposite poles; in telophase, they arrive at the poles and the chromosome de-condense as the nucleus reforms.