Freshwater animals are not osmoconformers because

Options

A. they require large quantities of water to excrete ammonia
B. they are subjected to exosmosis due to which their body fluids become more concentrated
C. their body fluids would be too dilute to carry out life's processes
D. salts move passively from the surrounding medium into their bodies

Answer

**Step-by-Step Solution:**

1. **Understanding Osmoconformers**: Osmoconformers are organisms that maintain an internal environment that is isotonic (equal concentration) to their external environment. This means their body fluids have the same concentration of solutes as the surrounding water.

2. **Freshwater Animals' Environment**: Freshwater animals live in environments with very low salt concentrations. They are adapted to these low salinity conditions and are classified as stenohaline, meaning they cannot tolerate significant changes in salinity.

3. **Impact of Marine Environment**: When freshwater animals are exposed to a marine (saltwater) environment, the surrounding water is hypertonic, meaning it has a higher concentration of solutes (salts) compared to the body fluids of the freshwater animals.

4. **Exosmosis Process**: Due to the hypertonic nature of seawater, water will move out of the freshwater animal's body (exosmosis) to balance the concentration gradient. This leads to a loss of water from their bodies.

5. **Concentration of Body Fluids**: As water leaves the body, the concentration of salts in the body fluids increases, making them more concentrated. This change in concentration can disrupt cellular processes.

6. **Consequences of Increased Salinity**: The increase in salinity within the cells can lead to cell death, as freshwater animals are not adapted to handle such high levels of salt. This ultimately hinders their life processes and can result in death.

7. **Conclusion**: Therefore, freshwater animals are not osmoconformers because they are subjected to exosmosis when placed in a marine environment, leading to an increase in the concentration of their body fluids, which can be detrimental to their survival.

**Final Answer**: Freshwater animals are not osmoconformers because they are subjected to exosmosis due to which their body fluids become more concentrated.

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