Click on each checkpoint symbol to learn more about what happens during that checkpoint. The cell cycle is a regulated or controlled process. During the cell cycle, there are three checkpoints that make sure the cells are functioning properly and ready to move on to the next stage of the cycle. Scientists have discovered special proteins in the cell called cyclins. Cyclins regulate the timing of the eukaryotic cell cycle.
Three main chemical checkpoints have been discovered. There are the G1, G2, and M checkpoints. What happens at each stage is not completely understood but scientists do know that many of the checkpoints look for damages in DNA.
The image below shows the three main checkpoints in the cell cycle.
Click on each checkpoint symbol to learn more about what happens during that checkpoint.