Which of the following animals are not uricotelic?

Options

A. Reptiles and birds
B. Birds and land snails
C. Land snails and terrestrial insects
D. Aquatic insects and marine fishes

Answer

To determine which animals are not uricotelic, we need to understand the terms involved:

1. **Uricotelic Animals**: These are animals that excrete nitrogenous waste primarily in the form of uric acid. Examples include birds, reptiles, and land snails.

2. **Ammonotelic Animals**: These are animals that excrete nitrogenous waste primarily in the form of ammonia. Examples include aquatic insects and fish.

Now, let's analyze the options provided in the question step by step:

### Step 1: Analyze the first option - Reptiles and Birds
- **Reptiles**: These animals are uricotelic as they excrete uric acid.
- **Birds**: These are also uricotelic as they excrete uric acid.
- **Conclusion**: This option is incorrect because both reptiles and birds are uricotelic.

### Step 2: Analyze the second option - Birds and Land Snails
- **Birds**: As mentioned, birds are uricotelic.
- **Land Snails**: These are also uricotelic as they excrete uric acid.
- **Conclusion**: This option is incorrect because both birds and land snails are uricotelic.

### Step 3: Analyze the third option - Uric Acid and Terrestrial Insects
- **Uric Acid**: This indicates uricotelic animals.
- **Terrestrial Insects**: Many terrestrial insects are also uricotelic as they excrete uric acid.
- **Conclusion**: This option is incorrect because both components are uricotelic.

### Step 4: Analyze the fourth option - Aquatic Insects and Fishes
- **Aquatic Insects**: These are generally ammonotelic as they excrete ammonia.
- **Fishes**: Most fishes, especially marine ones, are also ammonotelic and excrete ammonia.
- **Conclusion**: This option is correct because both aquatic insects and fishes are not uricotelic; they are ammonotelic.

### Final Answer:
The animals that are not uricotelic are **Aquatic Insects and Fishes**.

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