Question

According to the universally accepted model of plasma membrane

• A. More extrinsic proteins are found on the outer face of membrane
• B. Extrinsic proteins show flip-flop movement
• C. Glycocalyx is exclusively present towards outer face of membrane
• D. Certain extrinsic proteins also help in transport across membrane

Answer 1

The correct option is A More extrinsic proteins are found on the outer face of membrane

The internal proteins are called intrinsic or integral proteins while the external ones are known as extrinsic or peripheral proteins. The integral or intrinsic proteins account for 70% of the total membrane proteins. Some lipids and extrinsic proteins present on the outer side possess small carbohydrate mol­ecules to form glycolipids and glycoproteins. They constitute glycocalyx or cell coat.

So, the correct option is 'Glycocalyx is exclusively present towards the outer face of membrane'.