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 structures found in the inner ear of vertebrates. They consist of three canals that are oriented at right angles to each other.

2. **Function of Semicircular Canals**: These canals are filled with a fluid called lymph. Their primary function is to help maintain balance and spatial orientation.

3. **Evaluating the Options**:
- **Option A: Detection of Change in Atmospheric Pressure**: This function is not performed by the semicircular canals. Instead, mechanoreceptors in the skin are responsible for detecting changes in atmospheric pressure.
- **Option B: Orientation of Animal with Regard to Sun**: This is also incorrect. Orientation with respect to the sun is managed by receptors in the brain, not the semicircular canals.
- **Option C: Maintenance of Balance When Organism is in Motion**: This is the correct function of the semicircular canals. They play a crucial role in maintaining balance when the body is in motion or standing still.

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

**Final Answer**: The semicircular canals in vertebrates are responsible for maintenance of balance when the organism is in motion.

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