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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M checkpoint
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G0 checkpoint
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Detailed explanation-1: -The G2/M checkpoint is controlled by Cdc2/cyclinB, and their negative regulators including p21Cip1 and p27 [9]. Weakened G2/M checkpoint under therapeutic setting may trigger cell death via mitotic catastrophe for cells with unrepairable DNA lesions and mitosis machinery.
Detailed explanation-2: -At the G2 checkpoint, the cell checks for: DNA damage. DNA replication completeness.
Detailed explanation-3: -Gap 2 Phase This last stage is all about prepping the cell for mitosis or meiosis. During G2, the cell has to grow some more and produce any molecules it still needs to divide. This includes assembly of the microtubules, which will make up an important structure called the spindle during mitosis.
Detailed explanation-4: -Two groups of proteins, called cyclins and cyclin-dependent kinases (Cdks), are responsible for the progress of the cell through the various checkpoints. The levels of the four cyclin proteins fluctuate throughout the cell cycle in a predictable pattern (Figure 2).