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 need to analyze each of the provided statements and identify the one that is incorrect.

### Step-by-Step Solution:

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

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

- **Statement 2**: "They are set at right angles to one another."
- This statement is also **true**. The three semicircular canals are oriented at right angles to each other, allowing them to detect rotational movements in different planes.

- **Statement 3**: "Both ends of each canal swell to form ampullae."
- This statement is **false**. Each semicircular canal has a swelling at one end called the ampulla, but not both ends. Only one end of each canal swells to form the ampulla.

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

3. **Conclusion**:
- The incorrect statement among the options given is **Statement 3**: "Both ends of each canal swell to form ampullae."

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

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