Sensory hair cells are present in

Options

A. Cristae
B. Maculae
C. Cochlea
D. All of these

Answer

### Step-by-Step Solution:

1. **Understanding Sensory Hair Cells**:
- Sensory hair cells are specialized cells that play a crucial role in the auditory and vestibular systems. They are responsible for converting mechanical stimuli (like sound waves) into electrical signals that can be interpreted by the brain.

2. **Function of Sensory Hair Cells**:
- The primary function of sensory hair cells is to amplify sound waves. They help in detecting sound vibrations and transducing this information into neural signals that are sent to the brain for processing.

3. **Locations of Sensory Hair Cells**:
- Sensory hair cells are found in several structures within the inner ear:
- **Cristae**: These are located in the ampullae of the semicircular canals and are involved in detecting rotational movements.
- **Maculae**: These are found in the utricle and saccule, which are responsible for detecting linear acceleration and the position of the head relative to gravity.
- **Cochlea**: This is the spiral-shaped organ responsible for hearing, where hair cells are located in the organ of Corti.

4. **Conclusion**:
- Since sensory hair cells are present in all the mentioned structures (Cristae, Maculae, and Cochlea), the correct answer to the question is "all of these".

### Final Answer:
- Sensory hair cells are present in **Cristae, Maculae, and Cochlea**. Therefore, the answer is **all of these**.

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