During which phase of mitosis do chromosomes align single file along the equator of a haploid cell?

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

Answer: (A)

Verified step by step guidance

1. Understand the phases of mitosis: Mitosis is divided into several phases—Prophase, Metaphase, Anaphase, and Telophase. Each phase has distinct characteristics and roles in cell division.
2. Focus on Metaphase: During Metaphase, chromosomes align single file along the equatorial plane (also called the metaphase plate) of the cell. This alignment ensures that each daughter cell will receive an identical set of chromosomes.
3. Compare with other phases: In Prophase, chromosomes condense and the nuclear envelope begins to break down. In Anaphase, sister chromatids are pulled apart to opposite poles of the cell. In Telophase, the nuclear envelope reforms around the separated chromatids, and the cell begins to divide.
4. Recognize the key feature of Metaphase: The single-file alignment of chromosomes along the equator is unique to Metaphase and does not occur in the other phases.
5. Conclude that the correct phase for single-file chromosome alignment along the equator is Metaphase.