AP BIOLOGY

Detailed explanation-1: -The two copies of a chromosome are called sister chromatids. The sister chromatids are identical to one another and are attached to each other by proteins called cohesins.

Detailed explanation-2: -Because each duplicated chromosome consists of two identical sister chromatids joined at a point called the centromere, these structures now appear as X-shaped bodies when viewed under a microscope. Several DNA binding proteins catalyze the condensation process, including cohesin and condensin.

Detailed explanation-3: -Two chromatids are required to form a chromosome. A chromatid is one of two identical structures of chromosomes which already undergo replication. Two chromatids in a chromosome are known as sister chromatids.

Detailed explanation-4: -Sister chromatids are two identical copies of the same chromosome formed by DNA replication, attached to each other by a structure called the centromere. During cell division, they are separated from each other, and each daughter cell receives one copy of the chromosome.