Answer:
Internal and external regulators are two types of proteins that regulate the cell cycle. Internal regulators allow the cell cycle to proceed only after certain events occur. External regulators speed up or slow down the cell cycle.
Explanation:
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The two types of proteins that regulate the cell cycle are Cyclins and Cyclin-dependent Kinases (CDKs). These two groups of proteins are responsible for the progress of the cell through various checkpoints.
What are Proteins?
Proteins are made up of hundreds or thousands of smaller units called Amino acids. They are large, complex molecules that play many critical roles in the body. They do most of the work in cells and are required for the structure, function, and regulation of the body’s tissues and organs.
Cyclins regulate the cell cycle only when they are bound to Cdks and become fully active. The Cdk/cyclin complex must be phosphorylated, which further initiates other proteins to be phosphorylated that advances the cell cycle.
Retinoblastoma (Rb), is another group of tumor-suppressor proteins that regulates the cell cycle by monitoring the cell size.
Therefore, there are two types of proteins that regulate the process of the cell cycle are Cyclins and Cyclin-dependent Kinases (CDKs).
To learn more about the Cell cycle, refer to the link:
https://brainly.com/question/8283140
