Trimethylamine is the excrtory product in

Options

A. Marine teleosts
B. Freshwater fishes
C. Molluscs
D. Amphibians

Answer

### Step-by-Step Text Solution

1. **Understanding the Question**: The question asks which group of organisms excretes trimethylamine as a waste product.

2. **Identifying the Options**: The options provided are:
- Marine teleosts
- Freshwater fishes
- Mollusks
- Amphibians

3. **Examining Marine Teleosts**: Marine teleosts, such as catfish, are known to excrete trimethylamine. This is a key point because it indicates that marine teleosts have a unique method of nitrogenous waste excretion.

4. **Understanding the Process**: The process involves the conversion of ammonia, which is toxic, into trimethylamine through a process called methylation. This conversion is crucial for the survival of these marine organisms in their aquatic environment.

5. **Further Conversion**: Trimethylamine is then oxidized in the presence of oxygen to form trimethylamine oxide (TMAO). This compound is water-soluble and non-toxic, making it a suitable excretory product.

6. **Analyzing Other Options**:
- **Freshwater Fishes**: Species like rohu and katla excrete urea, not trimethylamine.
- **Mollusks**: Terrestrial mollusks also convert nitrogenous waste into urea, not trimethylamine.
- **Amphibians**: Amphibians like frogs primarily excrete urea as well.

7. **Conclusion**: Based on the information analyzed, trimethylamine is specifically the excretory product in marine teleosts.

### Final Answer
Trimethylamine is the excretory product in marine teleosts.

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