The true sense of equilibrium in mammals are situated in the

Options

A. Utriculus
B. Sacculus
C. Semicircle ducts
D. Cochlea.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where the true sense of equilibrium is situated in mammals. This refers to the anatomical structures responsible for balance.

2. **Identifying Relevant Structures**: In mammals, the inner ear contains several structures that are involved in maintaining balance. The key structures include the utriculus, sacculus, semicircular ducts, and cochlea.

3. **Focusing on Semicircular Ducts**: Among these structures, the semicircular ducts (or canals) are specifically designed to detect rotational movements and help maintain balance. There are three semicircular canals oriented in different planes, which allows for the detection of movement in multiple directions.

4. **Mechanism of Action**: Each semicircular duct is filled with a fluid called endolymph and lined with sensory hair cells (cilia). When the head moves, the fluid within these ducts also moves, causing the cilia to bend. This bending generates nerve impulses that are sent to the brain, providing information about the body's position and movement.

5. **Conclusion**: Based on the information provided, the true sense of equilibrium in mammals is primarily situated in the semicircular ducts.

**Final Answer**: The true sense of equilibrium in mammals is situated in the semicircular ducts.

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