Consider the following statement: “All present-day cells have arisen by an uninterrupted series of cell divisions...

Consider the following statement: “All present-day cells have arisen by an uninterrupted series of cell divisions extending back in time to the first cell division.” Is this strictly true? Why or Why not?

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Expert Solution

Yes this statement is true. During the cell division the parent cell divides into two daughter cells(mitosis) and 4 daughter cells (meiosis). Cell division is an integral part of the cell cycle, only if the cell which divides properly is allowed to progress further. To monitor this there are various checkpoints in the cell cycle like the cell growth checkpoint (occurs at the end of G1 phase which checks the size of the cell and also if the nutrients is supplied properly.), DNA synthesis checkpoint (occurs during S phase and checks if the DNA replication is done correctly) and the last mitosis checkpoint (occurs during the M phase and checks if the mitosis is complete). If any of this checkpoints criteria is not fulfilled then the cell is given a chance to repair and even so if the damage cannot be repaired the cell is sent for apoptosis. Hence the cell which cannot divide cannot be further progressed which means only the cell who have been produced with uninterrupted series of cell division exists.

gladiator answered 1 year ago

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