Insects excrete nitrogen as

Options

A. Uric acid
B. Guanine
C. Urea
D. Ammonia.

Answer

### Step-by-Step Solution:

1. **Identify the Question**: The question asks about the form in which insects excrete nitrogenous waste.

2. **Understand the Group**: Insects belong to the phylum Arthropoda. It is important to recognize that different groups of organisms have different methods of excreting nitrogen.

3. **Research Nitrogenous Waste in Insects**: Insects primarily excrete nitrogen in the form of uric acid. This is a key characteristic of insects and some other organisms.

4. **Define Uricotelic Organisms**: Organisms that excrete nitrogenous waste as uric acid are referred to as uricotelic organisms. Insects fall into this category.

5. **Evaluate the Options**:
- **Uric Acid**: Correct. Insects excrete nitrogen as uric acid.
- **Guanine**: Incorrect. No organisms excrete guanine as a nitrogenous waste.
- **Urea**: Incorrect. Urea is excreted by ureotelic organisms, primarily mammals.
- **Ammonia**: Incorrect. Ammonia is excreted by ammonotelic organisms, mainly aquatic organisms.

6. **Conclusion**: The correct answer to the question is that insects excrete nitrogen as **uric acid**.

### Final Answer:
Insects excrete nitrogen as **uric acid**.

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