SME
Grade 9 Science · Problem type
Which checkpoint stops it?
Use this for “A cell’s DNA is damaged before it is copied. Where in the cycle is it stopped?”
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Which checkpoint catches it?
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Assumptions
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Checkpoints are proteins that check the cell before it moves on to the next phase.
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A cell that fails a check pauses to repair the problem, or destroys itself by apoptosis.
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The cell cycle and its control, cancer, mitosis and meiosis
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