In which of the following animals kidneys are aglomerular ?

Options

A. Marine fishes
B. Desert amphibians
C. Both (1) and (2)
D. Desert rats

Answer

To determine which animals have aglomerular kidneys, we need to understand what aglomerular kidneys are and analyze the options provided.

### Step-by-Step Solution:

1. **Define Aglomerular Kidneys**:
Aglomerular kidneys are kidneys that lack glomeruli, which are the capillary networks responsible for filtering blood in the kidneys. In these kidneys, the filtration process that typically occurs in the glomeruli is absent.

**Hint**: Remember that aglomerular means "without glomeruli."

2. **Analyze the Options**:
We need to evaluate the options given in the question to see which animals have aglomerular kidneys.

**Hint**: Look for animals that have adaptations to their environments that might lead to the absence of glomeruli.

3. **Option 1 - Marine Fishes**:
Marine fishes live in environments with high salt concentrations. To manage this, they primarily use their gills for osmoregulation and do not rely heavily on their kidneys for filtration. Therefore, they have aglomerular kidneys.

**Hint**: Consider how living in a salty environment affects the need for kidney filtration.

4. **Option 2 - Desert Amphibians**:
Desert amphibians are adapted to arid environments where water conservation is crucial. They produce highly concentrated urine and do not require glomerular filtration, leading to the presence of aglomerular kidneys.

**Hint**: Think about how adaptations to conserve water might influence kidney structure.

5. **Option 3 - Desert Rats**:
Desert rats are mammals, and mammals typically have glomerular kidneys. They rely on glomerular filtration for waste removal, so they do not have aglomerular kidneys.

**Hint**: Recall that mammals generally possess glomerular kidneys.

6. **Conclusion**:
Based on the analysis, the animals that have aglomerular kidneys are marine fishes and desert amphibians. Therefore, the correct answer is both 1 and 2.

**Final Answer**: Marine fishes and desert amphibians have aglomerular kidneys.