CELL STRUCTURES AND FUNCTION
CELL CYCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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osmosis
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mitosis
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respiration
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mutation
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Detailed explanation-1: -If the DNA can be repaired, p53 activates other genes to fix the damage. If the DNA cannot be repaired, this protein prevents the cell from dividing and signals it to undergo apoptosis. By stopping cells with mutated or damaged DNA from dividing, p53 helps prevent the development of tumors.
Detailed explanation-2: -Activated p53 can halt cell division in both the G1 and G2 phases of the cell division cycle. G1 is the preparation phase of the cell before replication of its DNA and G2 prepares the cell for mitosis.
Detailed explanation-3: -The p53 gene is a type of tumor suppressor gene. Also called TP53 gene and tumor protein p53 gene.
Detailed explanation-4: -p53 also has a postmitotic checkpoint function critical for preventing DNA re-replication when the mitotic spindle is disrupted. Treatment of normal mouse fibroblasts with mitotic spindle-destabilizing drugs, such as nocodazole and colcemid, causes them to exit mitosis and arrest at the G1 phase with 4N DNA content.
Detailed explanation-5: -After accumulating in response to stressful events, the Xbp1 protein appears to suppress the cell cycle, the study suggests. The findings, published in the Journal of Cell Biology, appear to solve one long-standing mystery of the cell cycle.