Which structure helps in locomotion in ctenophores?

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about ctenophores, which are commonly known as comb jellies.

2. **Understand the Structure**: Ctenophores have a unique structure that is crucial for their movement. This structure consists of rows of ciliated plates.

3. **Describe the Structure**: These plates are known as ciliated comb plates. Ctenophores have eight external rows of these comb plates.

4. **Function of the Structure**: The primary function of the ciliated comb plates is locomotion. They beat in a coordinated manner, allowing the ctenophores to move through the water.

5. **Conclusion**: Therefore, the structure that helps in locomotion in ctenophores is the ciliated comb plates.

**Final Answer**: Ciliated comb plates help in locomotion in ctenophores.

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