As we've explored before, cell division is prone to errors. Checkpoints help prevent these errors from being passed on to daughter cells.
At the end of the G1 phase
- The cell is examined for DNA damage.
- The cell is also checked to make sure a sufficient amount of substrates are available in the cell.
During the G2 phase
- The cell is examined again for DNA damage.
- The cell is checked to make sure the DNA is complete and that DNA replication occurred correctly.
During mitosis
- The cell is checked to make sure the chromosomes are correctly distributed.