AP BIOLOGY

Detailed explanation-1: -At the G2 checkpoint, the cell checks for: DNA damage. DNA replication completeness.

Detailed explanation-2: -G2/M checkpoints include the checks for damaged DNA, unreplicated DNA, and checks that ensure that the genome is replicated once and only once per cell cycle. If cells pass these checkpoints, they follow normal transition to the M phase.

Detailed explanation-3: -The G2-phase checkpoint, also known as G2/M-phase checkpoint, has the function of preventing cells with damaged DNA, lasting from the G1 and S phases or generated in G2, from undergoing mitosis. The mechanisms acting during the G2-phase checkpoint converge on the inhibition of the mitotic complex CDK1-cyclin B.

Detailed explanation-4: -G2 checkpoint – DNA quality control After the second growth phase, the cell checks that the DNA was completely and correctly replicated during the S phase. If it passes it enters the M phase, and if it fails it tries to correct the errors. If the cell is unable to repair the DNA, it undergoes apoptosis.

Detailed explanation-5: -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.