Prometaphase is described by which statement?

• A. The nuclear envelope fragments and the spindle microtubules attach to kinetochores of the chromosomes
• B. Chromosomes line up at the middle of the cell
• C. The cell divides
• D. The chromosomes become visible

Answer: (A)

Prometaphase is the stage between prophase and metaphase where the nuclear envelope breaks down and spindle microtubules attach to kinetochores on the chromosomes. This attachment allows chromosomes to begin moving toward the center of the cell as the spindle exerts tension, setting up their eventual alignment at the metaphase plate. The other options describe later or earlier events: linings up at the middle occurs in metaphase, the cell dividing happens in cytokinesis, and chromosomes becoming visible occurs earlier in prophase when chromatin condenses.