Stomochord (Buccal diverticulum) is present in :-

Options

A. Amphioxus
B. Herdmania
C. Balanoglossus
D. Asterias

Answer

To answer the question about where the stomochord (buccal diverticulum) is present, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Term**: The stomochord is a structure that is often referred to as a buccal diverticulum. It is a flexible, tubular structure found in certain organisms.

2. **Identify the Organisms**: The question provides several options, which we need to evaluate to determine where the stomochord is present. The options are:
- Amphioxus
- Herdmania
- Blanoglossus
- Asterias

3. **Evaluate Each Option**:
- **Amphioxus**: This organism does not have a stomochord. Instead, it has a wheel organ located on the sides of its oral cavity.
- **Herdmania**: This organism also does not possess a stomochord. It undergoes retrogressive metamorphosis, which does not involve the development of a stomochord.
- **Blanoglossus**: This organism is a hemichordate and is known to have a buccal diverticulum, which is synonymous with the stomochord.
- **Asterias**: This is a common sea star (starfish) and does not have a stomochord.

4. **Conclusion**: Based on the evaluations, the only organism that possesses a stomochord (buccal diverticulum) is **Blanoglossus**. Therefore, the correct answer is option 3.

### Final Answer:
The stomochord (buccal diverticulum) is present in **Blanoglossus**.

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