How many of the following animals are ureotelic ?
[Shark , Human , Rohu , Skate Tadpole , Frog , Cockroach]

Options

A. Two
B. Three
C. Four
D. Five

Answer

To determine how many of the listed animals are ureotelic, we first need to understand what ureotelic means. Ureotelic animals excrete nitrogen primarily in the form of urea, which is less toxic than ammonia and allows for better water conservation.

Let's analyze each animal in the list:

1. **Shark**: Sharks are classified as ureotelic because they excrete urea. They are cartilaginous fish and have adapted to excrete urea to conserve water.

2. **Human**: Humans are also ureotelic. As mammals, they excrete nitrogenous waste primarily in the form of urea.

3. **Rohu**: Rohu is a type of fish. Most bony fish, including Rohu, excrete ammonia directly into the water rather than urea, so Rohu is not ureotelic.

4. **Skate**: Skates are similar to sharks and are also ureotelic, excreting urea.

5. **Tadpole**: Tadpoles primarily excrete ammonia, which is typical for many aquatic larvae. Therefore, tadpoles are not ureotelic.

6. **Frog**: Adult frogs are ureotelic as they excrete urea, while tadpoles excrete ammonia.

7. **Cockroach**: Cockroaches are not ureotelic; they excrete nitrogenous waste in the form of uric acid, which is typical for many terrestrial arthropods.

Now, let's summarize the ureotelic animals from the list:
- Shark: Ureotelic
- Human: Ureotelic
- Rohu: Not ureotelic
- Skate: Ureotelic
- Tadpole: Not ureotelic
- Frog: Ureotelic
- Cockroach: Not ureotelic

Counting the ureotelic animals:
- Shark: 1
- Human: 1
- Skate: 1
- Frog: 1

Total ureotelic animals = 4

**Final Answer**: 4 animals are ureotelic.