What is the primary function of carbohydrates in the cell membrane?

• A. Structural support
• B. Transport of molecules
• C. Energy storage
• D. Cell recognition and signaling

Answer: (D)

Verified step by step guidance

1. Understand the role of carbohydrates in the cell membrane: Carbohydrates are attached to proteins and lipids on the extracellular surface of the cell membrane, forming glycoproteins and glycolipids.
2. Recognize the function of glycoproteins and glycolipids: These molecules are involved in cell recognition and signaling, which are crucial for the immune response and communication between cells.
3. Differentiate between the options: Structural support is primarily provided by proteins and the cytoskeleton, transport of molecules is mainly facilitated by proteins, and energy storage is a function of carbohydrates in the form of glycogen or starch, not in the cell membrane.
4. Focus on cell recognition and signaling: Carbohydrates on the cell surface act as markers that can be recognized by other cells, playing a key role in processes like tissue formation and immune response.
5. Conclude that the primary function of carbohydrates in the cell membrane is cell recognition and signaling, which is essential for cellular communication and interaction.