Carbohydrates in cell membrane participate in

Options

A. transportation of materials
B. cell to cell recognition
C. catalysing reactions
D. all of the above

Answer

**Step-by-Step Solution:**

1. **Understanding Carbohydrates in Cell Membrane:**
- Carbohydrates in the cell membrane are not found alone; they are typically associated with proteins or lipids.
- When carbohydrates are attached to proteins, they form glycoproteins; when attached to lipids, they form glycolipids.

2. **Analyzing the Options:**
- The question provides four options regarding the role of carbohydrates in the cell membrane:
1. Transportation of materials
2. Cell-to-cell recognition
3. Catalyzing reactions
4. All of the above

3. **Evaluating Option 1 - Transportation of Materials:**
- Transportation of materials primarily involves transmembrane proteins.
- These transmembrane proteins do not have a direct connection with carbohydrates, making this option incorrect.

4. **Evaluating Option 2 - Cell-to-Cell Recognition:**
- Complex carbohydrates coat the cell surface and carry essential information.
- They act as sugar-specific receptors that help cells recognize each other, making this option correct.

5. **Evaluating Option 3 - Catalyzing Reactions:**
- Catalyzing reactions is primarily the role of enzymes, not carbohydrates.
- Since carbohydrates do not play a role in catalyzing reactions, this option is also incorrect.

6. **Evaluating Option 4 - All of the Above:**
- Since options 1 and 3 are incorrect, option 4 (All of the above) is also incorrect.

7. **Conclusion:**
- The correct answer is that carbohydrates in the cell membrane participate in **cell-to-cell recognition**.

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