CELL STRUCTURES AND FUNCTION
CELL CYCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Checkpoints repeat
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Checkpoints don’t function properly
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Mitosis is repeated
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Cells shrink
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Detailed explanation-1: -Unable to exercise checkpoint functions, the host cell divides uncontrollably, forming cancerous tumors. Deregulation of the cell cycle by large T antigen ensures progress to the S phase and unregulated co-replication of viral and host cell DNA.
Detailed explanation-2: -If the cell cycle checkpoints fail, cells that are not replicating correctly will be allowed to continue to grow and multiply. This is dangerous because the cell cycle mutations that are causing the failure can be passed on through the cell lineage.
Detailed explanation-3: -Genetic analysis of human cancers has revealed that proteins involved in the G1/S checkpoint are inactivated in the majority of cases, and that alterations of the DNA damage checkpoint are likely to be responsible for resistance of tumour cells to chemotherapic agents or irradiation.