PATHOLOGY

Detailed explanation-1: -If the checkpoint mechanisms detect problems with the DNA, the cell cycle is halted, and the cell attempts to either complete DNA replication or repair the damaged DNA. If the damage is irreparable, the cell may undergo apoptosis, or programmed cell death 2.

Detailed explanation-2: -If a checkpoint fails or if a cell suffers physical damage to chromosomes during cell division, or if it suffers a debilitating somatic mutation in a prior S phase, it may selfdestruct in response to a consequent biochemical anomaly. This is another example of apoptosis.

Detailed explanation-3: -The activation of the DNA damage checkpoint restrains the mitotic entry of cells containing DNA adducts by triggering a transduction pathway that ends up taking over the control of the cell cycle, thus blocking cells in G2/M.

Detailed explanation-4: -A DNA damage checkpoint is a pause in the cell cycle that is induced in response to DNA damage to ensure that the damage is repaired before cell division resumes. Proteins that accumulate at the damage site typically activate the checkpoint and halt cell growth at the G1/S or G2/M boundaries.

Detailed explanation-5: -The G2 Checkpoint As at the G1 checkpoint, cell size and protein reserves are assessed. However, the most important role of the G2 checkpoint is to ensure that all of the chromosomes have been replicated and that the replicated DNA is not damaged.