In kidney, nephrostomes are functional in

Options

A. Tadpole
B. Adult Frog
C. Cockroach
D. Rabbit

Answer

To solve the question regarding the function of nephrostomes in the kidney, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Term "Nephrostomes":**
- Nephrostomes are specialized structures found in certain organisms. They are ciliated, funnel-shaped structures that play a role in excretion.

2. **Identify the Function of Nephrostomes:**
- The primary function of nephrostomes is to help in the movement of water and metabolic waste towards the kidneys. The cilia inside the nephrostomes assist in this process by creating a current that pushes these substances.

3. **Analyze the Options Given:**
- The options provided are:
- A) Tadpole
- B) Adult Frog
- C) Cockroach
- D) Rabbit

4. **Evaluate Each Option:**
- **Tadpole:** Nephrostomes are functional in tadpoles as they have a larval form of excretion that utilizes these structures.
- **Adult Frog:** In adult frogs, nephrostomes are not functional as they have a different excretory system.
- **Cockroach:** Cockroaches do not possess kidneys; instead, they have a different excretory system (Malpighian tubules).
- **Rabbit:** Rabbits have a more complex kidney structure and do not utilize nephrostomes.

5. **Conclude the Correct Answer:**
- Based on the analysis, the correct answer is **A) Tadpole**, as nephrostomes are functional in this stage of development.

### Final Answer:
Nephrostomes are functional in **tadpole**.