Endolymph is seen in

Options

A. Scala vestibuli
B. Scala tympani
C. Both 1 and 2
D. Scala media

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where endolymph is found. Endolymph is a fluid in the inner ear that plays a crucial role in hearing and balance.

2. **Identifying the Options**: The options given are:
- Option 1: Scala vestibuli
- Option 2: Scala tympani
- Option 3: Both scala vestibuli and scala tympani
- Option 4: Scala media

3. **Analyzing Scala Vestibuli and Scala Tympani**:
- The scala vestibuli and scala tympani are parts of the cochlea in the inner ear.
- Both of these structures contain perilymph, which is a fluid that is high in sodium (Na+) and low in potassium (K+).
- Since the question specifically asks for endolymph, these options can be eliminated.

4. **Identifying Scala Media**:
- The scala media, also known as the cochlear duct, is another part of the cochlea.
- It is filled with endolymph, which is characterized by being low in sodium (Na+) and high in potassium (K+).
- Therefore, scala media is the correct answer as it contains endolymph.

5. **Conclusion**: Based on the analysis, the correct option for the question is option number four, which is the scala media.

**Final Answer**: The endolymph is seen in the scala media.

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