Uric acid excretion is an adaptation for

Options

A. Water conservation
B. Water removal
C. Osmoregulation
D. None

Answer

**Step-by-Step Solution:**

1. **Understanding Nitrogenous Waste**:
- Nitrogenous wastes are byproducts of protein metabolism and are excreted in three main forms: ammonia, urea, and uric acid.
- Each type of nitrogenous waste has different water requirements for its excretion.

2. **Ammonia Excretion**:
- Ammonia is highly toxic and requires a large amount of water to dilute it for safe excretion.
- Organisms that excrete ammonia are called ammonotelic organisms, which include most aquatic animals like fish and amphibians.

3. **Urea Excretion**:
- Urea is less toxic than ammonia and requires a moderate amount of water for excretion.
- Organisms that excrete urea are known as ureotelic organisms, which include mammals and some amphibians.

4. **Uric Acid Excretion**:
- Uric acid is the least toxic and requires the least amount of water for excretion.
- Organisms that excrete uric acid are termed uricotelic organisms. This includes birds, reptiles (like desert lizards), and some insects.

5. **Adaptation for Water Conservation**:
- The ability to excrete uric acid is an adaptation that allows organisms to conserve water, making it particularly advantageous in arid environments where water is scarce.
- For example, desert lizards and birds can excrete uric acid with minimal water loss, thus conserving water.

6. **Conclusion**:
- Based on the information, uric acid excretion is primarily an adaptation for water conservation. Therefore, the correct answer to the question is "water conservation."

**Final Answer**: Uric acid excretion is an adaptation for water conservation.

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