What is osphradium? Give its function.

Explanation

### Step-by-Step Text Solution:

1. **Definition of Osphradium**:
- Osphradium is a specialized sensory organ found in certain mollusks. It functions as a chemoreceptor, which means it is capable of detecting chemical substances in the environment.

2. **Location**:
- The osphradium is typically located near the mouth of the mollusk. This positioning allows it to effectively sample the water that flows into the organism.

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