Which are not ureotelic

Options

A. Mammals
B. Terrestrial amphibians
C. Aquatic insects
D. Bird/Snake

Answer

To determine which organisms are not ureotelic, we need to understand the terms involved and analyze the options provided.

### Step-by-Step Solution:

1. **Understanding Ureotelic Organisms**:
- Ureotelic organisms are those that excrete urea as their primary nitrogenous waste product. Urea is less toxic than ammonia and can be stored in the body for longer periods.

2. **Identifying Ureotelic Organisms**:
- Mammals: They excrete urea and are therefore ureotelic.
- Terrestrial Amphibians: They also excrete urea, making them ureotelic.
- Aquatic Insects: These organisms excrete urea as well, classifying them as ureotelic.

3. **Analyzing the Remaining Options**:
- Birds: They excrete uric acid instead of urea. This makes them uricotelic, not ureotelic.
- Snakes: Similar to birds, snakes also excrete uric acid, classifying them as uricotelic.

4. **Conclusion**:
- From the analysis, we conclude that birds and snakes are not ureotelic organisms. They are uricotelic because they excrete uric acid as their nitrogenous waste product.

### Final Answer:
Birds and snakes are not ureotelic; they are uricotelic.

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