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: -The centromere is the point at which two chromatids of a chromosome are held together.

Detailed explanation-3: -A sister chromatid is either one of the two chromatids of the same chromosome joined together by a common centromere. A pair of sister chromatids is called a dyad.

Detailed explanation-4: -Chromosomes and cell division After DNA replication, each chromosome now consists of two physically attached sister chromatids. After chromosome condensation, the chromosomes condense to form compact structures (still made up of two chromatids).

Detailed explanation-5: -Each chromosome has two short arms called p arms and two long arms called q arms. These arms are held together at the center by the centromere. The tips of the chromosome are capped by sections of DNA called telomeres.