What is the name of the region of a chromosome that attaches to spindle fibers during cell division?

• A. Centromere
• B. Chromosome
• C. Chromatid
• D. Chromatin

Answer: (A)

During cell division, spindle fibers attach to the chromosome at the centromere, the constricted region where the two sister chromatids are held together. Kinetochores, protein structures that form at the centromere, are the actual contact points for the spindle microtubules. This connection allows the chromosomes to be guided and pulled apart as the cell progresses through metaphase to anaphase, ensuring each daughter cell receives a complete set of chromosomes.

For context, a chromosome is the entire structure, a chromatid is one of the two identical copies of a replicated chromosome, and chromatin is the uncondensed DNA–protein complex found when the chromosome is not yet condensed for division.