What are 4 functions of cholesterol in the plasma membrane?

Cholesterol has four main functions in the plasma membrane:

1. Cell membrane fluidity: Cholesterol helps maintain the fluidity and flexibility of the cell membrane. It prevents the membrane from becoming too rigid or too fluid, ensuring that it can function properly.

2. Membrane permeability: Cholesterol reduces the permeability of the plasma membrane to small molecules, such as water and ions. This helps maintain the cell's internal environment and prevents it from losing essential molecules.

3. Signal transduction: Cholesterol is involved in the signal transduction process, which allows cells to respond to external stimuli. It helps transmit signals from the cell surface to the inside of the cell.

4. Membrane protein function: Cholesterol is essential for the proper functioning of membrane proteins. It helps stabilize these proteins and ensures that they can interact with each other properly.