Plasma membrane helps in

Options

A. osmoregulation
B. protein synthesis
C. nucleic acid synthesis
D. transportation of only water in and out of cell

Answer

**Step-by-Step Solution:**

1. **Understanding the Plasma Membrane**: The plasma membrane is a phospholipid bilayer that surrounds the cell, providing structure and protection. It is composed of phospholipids with embedded proteins.

2. **Semi-permeable Nature**: The plasma membrane is semi-permeable, meaning it allows certain substances to pass through while restricting others. This characteristic is crucial for maintaining the internal environment of the cell.

3. **Role in Osmoregulation**: One of the primary functions of the plasma membrane is osmoregulation. This process involves regulating the movement of water and solutes in and out of the cell to maintain homeostasis. The plasma membrane allows the free flow of water (solvent) while selectively allowing certain solutes to pass through.

4. **Evaluating the Options**:
- **Option 1: Osmoregulation** - This is correct as the plasma membrane plays a vital role in regulating the flow of water and solutes.
- **Option 2: Protein Synthesis** - This is incorrect. Protein synthesis occurs in ribosomes, not directly at the plasma membrane.
- **Option 3: Nucleic Acid Synthesis** - This is also incorrect. Nucleic acid synthesis occurs in the nucleus and cytoplasm, not at the plasma membrane.
- **Option 4: Transportation of only water** - This is misleading. While the plasma membrane does regulate water transport, it also regulates the transport of various solutes, not just water. Therefore, this option is incorrect.

5. **Conclusion**: The correct answer is that the plasma membrane helps in osmoregulation.

**Final Answer**: The plasma membrane helps in osmoregulation.

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