AP BIOLOGY

Detailed explanation-1: -In anaphase I, the homologues are pulled apart and move apart to opposite ends of the cell. The sister chromatids of each chromosome, however, remain attached to one another and don’t come apart. Finally, in telophase I, the chromosomes arrive at opposite poles of the cell.

Detailed explanation-2: -Anaphase I: In anaphase I, the attachment of the spindle fibers is complete. The homologous chromosomes are pulled apart and move towards opposite ends of the cell. Do not confuse this with the pulling apart of sister chromatids! This is the point in which reduction occurs with 23 chromosomes moving to each pole.

Detailed explanation-3: -Chromosomes move poleward in anaphase along stationary microtubules that coordinately disassemble from their kinetochore ends. J Cell Biol (1987) 104 (1): 9–18. During the movement of chromosomes in anaphase, microtubules that extend between the kinetochores and the poles shorten.

Detailed explanation-4: -Figure 3: During anaphase I, the homologous chromosomes are pulled toward opposite poles of the cell. During anaphase I, the microtubules disassemble and contract; this, in turn, separates the homologous chromosomes such that the two chromosomes in each pair are pulled toward opposite ends of the cell (Figure 3).

Detailed explanation-5: -During anaphase 1, homologous chromosomes separate and move to opposite ends of the cell. With anaphase 2, the sister chromatids separate in much the same manner as mitotic anaphase. Because the separation of genetic material occurs during anaphase, this step needs to be tightly regulated.