NEET BIOLOGY

Detailed explanation-1: -In mitosis, the spindle assembly checkpoint (SAC) controls the proper attachment to and alignment of chromosomes on the spindle. The SAC detects errors and induces a cell cycle arrest in metaphase, preventing chromatid separation.

Detailed explanation-2: -The M checkpoint is also known as the spindle checkpoint: here, the cell examines whether all the sister chromatids are correctly attached to the spindle microtubules.

Detailed explanation-3: -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.

Detailed explanation-4: -The M checkpoint occurs near the end of the metaphase stage of karyokinesis. The M checkpoint is also known as the spindle checkpoint, because it determines whether all the sister chromatids are correctly attached to the spindle microtubules.

Detailed explanation-5: -The primary G1/S cell cycle checkpoint controls the commitment of eukaryotic cells to transition through the G1 phase to enter into the DNA synthesis S phase.