CELL STRUCTURES AND FUNCTION
CELL CYCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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G1 checkpoint
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G2 checkpoint
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S checkpoint
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M checkpoint
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Detailed explanation-1: -The main prerequisite for clearance at the G2 checkpoint is accurate and complete DNA replication. The correct option is (c).
Detailed explanation-2: -What is the main prerequisite for clearance at the G2 checkpoint? An accurate and complete DNA replication has occurred.
Detailed explanation-3: -At the G2 checkpoint, DNA is checked to ensure that all chromosomes were duplicated and that there are no mistakes in newly synthesized DNA. Additionally, cell size and energy reserves are evaluated. The M checkpoint confirms the correct attachment of the mitotic spindle fibers to the kinetochores.
Detailed explanation-4: -DNA replication does not occur during the G2 phase of interphase.
Detailed explanation-5: -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.