Semicircular canals exhibit all these features except :

Options

A. They from part of vestibular apparatus
B. They are set at right angles to one another
C. Both ends of each canal swell to From ampullae
D. Each ampulla is concerned with maintenance of balance and posture of the body

Answer

To solve the question regarding the features of semicircular canals, we will analyze each of the provided statements one by one.

### Step-by-Step Solution:

1. **Understanding Semicircular Canals**:
- Semicircular canals are part of the inner ear and play a crucial role in maintaining balance and spatial orientation.

2. **Evaluating the Statements**:
- **Statement 1**: "They form part of vestibular apparatus."
- **Analysis**: This statement is true. The semicircular canals are indeed components of the vestibular apparatus, which is responsible for balance.

- **Statement 2**: "They are set at right angles to one another."
- **Analysis**: This statement is also true. The three semicircular canals are oriented in three different planes and are set at right angles to each other.

- **Statement 3**: "Both ends of each canal swell to form ampullae."
- **Analysis**: This statement is false. Only one end of each semicircular canal swells to form an ampulla. The other end does not swell.

- **Statement 4**: "Each ampulla is concerned with maintenance of balance and posture of the body."
- **Analysis**: This statement is true. The ampullae contain sensory receptors that help in maintaining balance and posture.

3. **Conclusion**:
- The only statement that is incorrect regarding the features of semicircular canals is Statement 3: "Both ends of each canal swell to form ampullae." Therefore, this is the answer to the question.

### Final Answer:
The semicircular canals exhibit all these features except: "Both ends of each canal swell to form ampullae."

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