An Amoeba survives in a hypotonic solution that destroys a human RBC. It is due to

Options

A. membrane permeability of Amoeba is much more than the membrane of a RBC.
B. Amoeba has water expelling contractile vacuoles
C. both (1) and (2) are correct
D. amoeba has a rigid wall

Answer

**Step-by-Step Solution:**

1. **Understanding Hypotonic Solutions:**
- A hypotonic solution is one where the concentration of solutes outside the cell is lower than that inside the cell. This causes water to move into the cell by osmosis.

2. **Effect on Red Blood Cells (RBCs):**
- When human red blood cells (RBCs) are placed in a hypotonic solution, water enters the cells. Since RBCs do not have a rigid cell wall, they can swell and eventually burst (hemolysis) due to the excess water.

3. **Effect on Amoeba:**
- Amoeba, on the other hand, is a unicellular organism that also experiences water influx in a hypotonic environment. However, amoebas possess specialized structures called contractile vacuoles.

4. **Role of Contractile Vacuoles:**
- Contractile vacuoles help amoebas expel excess water that enters the cell. This adaptation allows amoebas to survive in hypotonic solutions without bursting.

5. **Comparison of Membrane Permeability:**
- The membrane of an amoeba is more permeable and adaptable to changes in the environment compared to the rigid membrane of RBCs. This difference in membrane properties is crucial for their survival in hypotonic conditions.

6. **Conclusion:**
- Therefore, the ability of amoeba to survive in hypotonic solutions, unlike human RBCs, is primarily due to the presence of contractile vacuoles and the differences in membrane permeability.

**Final Answer:**
An amoeba survives in a hypotonic solution that destroys a human RBC due to the presence of contractile vacuoles that expel excess water, and the greater membrane permeability of amoeba compared to RBCs.

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