Question

which of the following is not a major function of proteins in the cell membrane?
acting as receptors
forming the entire glycocalyx
anchoring cells to other structures
forming channels

Explanation:

1. Analyze each option:

• Acting as receptors: Membrane proteins can act as receptors (e.g., for hormones or neurotransmitters), so this is a function.
• Forming the entire glycocalyx: The glycocalyx is made of glycolipids, glycoproteins, and carbohydrates. Proteins are part of it (glycoproteins) but don't form the entire glycocalyx (includes other components), so this is not a major function of proteins alone.
• Anchoring cells: Membrane proteins (like integrins) anchor cells to extracellular structures, so this is a function.
• Forming channels: Channel proteins form channels for ion or molecule transport, so this is a function.

Answer:

B. forming the entire glycocalyx