Final answer:
Kinase is an internal factor that controls the cell cycle by regulating the progression of the cell cycle through phosphorylation.
Step-by-step explanation:
An example of an internal factor that controls the cell cycle is kinase. Kinases are a type of enzyme that regulate the progression of the cell cycle by adding phosphate groups to other proteins. This phosphorylation process triggers specific events in the cell cycle, such as the transition from one phase to another. For example, cyclin-dependent kinases (CDKs) are responsible for controlling the cell cycle checkpoints and ensuring the proper timing of cell division.
Learn more about internal factors that control the cell cycle