A gymnast is able to balance his body upside down even in the total darkness because of

Options

A. Vestibular apparatus
B. Tectorial membrane
C. Organ of corti
D. Cochlea

Answer

To solve the question about why a gymnast can balance his body upside down even in total darkness, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks why a gymnast can maintain balance in total darkness. This implies that the answer relates to a sensory system that does not rely on visual cues.

2. **Identifying Relevant Body Parts**: The ear is a key structure involved in balance. The ear consists of three parts: the outer ear, the middle ear, and the inner ear.

3. **Focusing on the Inner Ear**: The inner ear is particularly important for balance. It contains a structure known as the labyrinth, which is divided into two parts: the bony labyrinth and the membranous labyrinth.

4. **Understanding the Membranous Labyrinth**: The membranous labyrinth contains several important components, including the cochlear duct, semicircular ducts, saccule, and utricle. These structures are crucial for maintaining balance and equilibrium.

5. **Role of the Vestibular Apparatus**: The vestibular apparatus, which is part of the membranous labyrinth, is specifically responsible for the sense of equilibrium and balance. It detects changes in head position and motion, allowing the gymnast to maintain balance even without visual input.

6. **Conclusion**: Therefore, the gymnast is able to balance his body upside down in total darkness because of the vestibular apparatus, which is responsible for the sense of balance.

### Final Answer:
The gymnast is able to balance his body upside down even in total darkness because of the **vestibular apparatus**.

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