Semicircular canals in vertebrate are responsible for :-

Options

A. Detection of change in atmospheric pressure.
B. Orientation of animal with regard to sun
C. Maintenance of balance when organism is in motion.
D. Regulation of speed of animal.

Answer

**Step-by-Step Solution:**

1. **Understanding Semicircular Canals**: The semicircular canals are part of the inner ear in vertebrates. They consist of three fluid-filled tubes arranged in different planes.

2. **Function of Semicircular Canals**: The primary function of the semicircular canals is to detect rotational movements of the head. They play a crucial role in maintaining balance and spatial orientation.

3. **Options Analysis**:
- **Detection of change in atmospheric pressure**: This function is not related to the semicircular canals; it is more associated with other structures in the ear.
- **Orientation of animals with regard to the sun**: While animals may use various cues for orientation, this is not the primary function of the semicircular canals.
- **Maintenance of balance when the organism is in motion**: This is the correct function of the semicircular canals. They help the body maintain balance during movement by detecting changes in head position and motion.
- **Regulation of speed**: This is not a function of the semicircular canals; speed regulation is more related to voluntary muscle control.

4. **Conclusion**: Based on the analysis of the options, the semicircular canals are responsible for the maintenance of balance when the organism is in motion.

**Final Answer**: Maintenance of balance when the organism is in motion.

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