Extenal coat composed of cellulose like materila occurs in

Options

A. hemichordata
B. urochordata
C. cephalochoradata
D. cyclostomata

Answer

To solve the question "External coat composed of cellulose-like material occurs in," we will analyze the options provided: hemichordate, urochordate, cephalochordate, and cyclostomata.

### Step-by-Step Solution:

1. **Understanding the Options**:
- **Hemichordate**: These are worm-like animals that do not possess an external coat made of cellulose-like material.
- **Urochordate**: Also known as tunicates, these organisms have an external coat that is indeed composed of cellulose-like material.
- **Cephalochordate**: These organisms do not have an external coat made of cellulose-like material.
- **Cyclostomata**: This group includes jawless fish and does not have an external coat made of cellulose-like material.

2. **Eliminating Incorrect Options**:
- Since hemichordates and cephalochordates do not have the external coat, we can eliminate these two options.
- Cyclostomata also do not have this characteristic, so it can be excluded as well.

3. **Identifying the Correct Answer**:
- The only group left is the **urochordates**, which are characterized by their external coat made of cellulose-like material. This coat is what gives them the name "tunicates."

4. **Conclusion**:
- Therefore, the correct answer to the question is **urochordate**.

### Final Answer:
The external coat composed of cellulose-like material occurs in **urochordates**.

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