AP BIOLOGY

Detailed explanation-1: -A chromatid is one of the two identical halves of a chromosome that has been replicated in preparation for cell division. The two “sister” chromatids are joined at a constricted region of the chromosome called the centromere.

Detailed explanation-2: -After replication there are a total of 92 sister chromatids in each cell. There are 46 individual chromosomes in each cell. Metaphase: During metaphase, each of the 46 chromosomes line up along the center of the cell at the metaphase plate.

Detailed explanation-3: -A pair of sister chromatids is called a dyad.

Detailed explanation-4: -The sister chromatids are identical to one another and are attached to each other by proteins called cohesins. The attachment between sister chromatids is tightest at the centromere, a region of DNA that is important for their separation during later stages of cell division.

Detailed explanation-5: -Following DNA replication (middle panels) “Watson” and Crick“ DNA template strands are copied to yield two sister chromatids with identical DNA sequence.