What term refers to the region found at the center of a chromosome where the sister chromatids are held together?

• A. Centromere
• B. Telomere
• C. Chromatid
• D. Kinetochore

Answer: (A)

The centromere is the region at the center of a chromosome where the sister chromatids are held together after DNA replication. It is the site where cohesin proteins keep the chromatids together and where the kinetochore—a protein structure that attaches spindle fibers—forms to enable proper alignment and separation during cell division. Telomeres are the protective ends of chromosomes, not the central holding region. A chromatid refers to one copy of the duplicated chromosome, not the region itself. A kinetochore is the protein complex at the centromere that interfaces with spindle microtubules, facilitating movement, but the question points to the actual region that keeps the two chromatids joined, which is the centromere.