Dunaliella is able to live under saline conditions by storing

Options

A. Glycerol
B. Sorbitol
C. Proline
D. Starch

Answer

**Step-by-Step Solution:**

1. **Understanding the Organism**: Dunaliella is a type of green microalgae that thrives in hypersaline environments, such as salt lakes.

2. **Identifying the Challenge**: In saline conditions, the external environment has a higher concentration of solutes (salts) compared to the internal fluids of the organism. This creates a tendency for water to move out of the cells through a process called exosmosis.

3. **Mechanism of Survival**: To survive in these conditions, Dunaliella must prevent excessive loss of water. This is achieved by increasing the osmotic pressure of its internal fluids.

4. **Role of Glycerol**: Dunaliella stores glycerol, a type of sugar alcohol, in large amounts. Glycerol acts as an osmotic agent, which helps to balance the osmotic pressure between the internal fluids of the algae and the external saline environment.

5. **Conclusion**: By storing glycerol, Dunaliella effectively increases the osmotic pressure of its body fluids, preventing the loss of water through exosmosis and allowing it to thrive in hypersaline conditions.

**Final Answer**: Dunaliella is able to live under saline conditions by storing glycerol.

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