Cdk inhibitors inhibit the function of cyclin-dependent protein kinases. Different inhibitors display varying mechanisms of Cdk inhibition. Which of the following might a Cdk inhibitor block in order to block Cdk function?
a. cyclin binding
b. ATP binding
c. substrate binding
d. movement of the T loop into the active site

The correct answer is  A) Cyclin Binding.                                                  

Explanation:

A CDK binds a regulatory protein called a cyclin. Without cyclin, CDK has little kinase activity.

Cyclin is a family of proteins that control the progression of a cell through the cell replication or reproduction cycle by activating cyclin-dependent kinase (CDK) enzymes or group of enzymes required for synthesis of cell cycle.

Molecular 'brakes' serve the purpose of restricting or regulating the growth of cells. When cell grow uncontrollably and rapidly, it is most times due to a malfunctioning molecular brake. Thus leading to Cancer or cancerous growth. The molecular brakes which regulate the growth of cells and permit them to divide only when they are needed to replace old ones are a group of enzymes referred to as cyclin-dependent kinases (CDKS)

Many cancers grow rapidly and uncontrollably because their cells overrun the molecular brakes that usually permit cell to divide only when they are needed to replace old ones. These brakes are regulated by a group of enzymes known as cyclin-dependent kinases (CDKs)

A CDK (cyclin-dependent kinase) inhibitor is any chemical that inhibits the function of CDKs.  

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