Excretory organ of hemichordates is

Options

A. renette gland
B. nephridia
C. proboscis gland
D. flame cells

Answer

To determine the excretory organ of hemichordates, we can follow these steps:

### Step 1: Understand the Organisms
Hemichordates are a group of marine animals that exhibit certain unique features. They are not as commonly known as other animal groups, so it's important to clarify what they are.

### Step 2: Review the Options
The options provided for the excretory organ are:
1. Rennet gland
2. Nephridia
3. Proboscis gland
4. Flame cell

### Step 3: Analyze Each Option
- **Rennet gland**: This is primarily associated with the digestive system in some animals, particularly in young mammals, and is not an excretory organ.

- **Nephridia**: These are excretory structures found in annelids (like earthworms) and are not present in hemichordates.

- **Flame cell**: These are excretory cells found in flatworms (phylum Platyhelminthes) and are not related to hemichordates.

- **Proboscis gland**: This is known to be the excretory organ in hemichordates. It helps in the removal of waste materials from their bodies.

### Step 4: Conclusion
Based on the analysis of the options, the correct answer is that the excretory organ of hemichordates is the **proboscis gland**.

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