AP BIOLOGY

Detailed explanation-1: -The spindle checkpoint ensures the fidelity of chromosome transmission by delaying anaphase until all chromatid pairs have formed proper links to the mitotic spindle. Sister chromatids attach to spindle microtubules (MTs) via kinetochores, which are multiprotein complexes that assemble on centromeric (CEN) DNA.

Detailed explanation-2: -The cell goes through an important checkpoint to ensure that all of the chromosomes are attached to the spindle and ready to be divided before it proceeds with division. Next, during anaphase, the chromosomes are simultaneously separated and pulled by the spindle to opposite poles of the cell.

Detailed explanation-3: -The M phase checkpoint ensures that all chromosomes are attached to the mitotic spindle.

Detailed explanation-4: -The spindle checkpoint occurs during the M phase. Scheme showing cell cycle progression between prometaphase and anaphase.

Detailed explanation-5: -The spindle checkpoint is a key regulator of chromosome segregation in mitosis and meiosis. Its function is to prevent precocious anaphase onset before chromosomes have achieved bipolar attachment to the spindle.