Macula densa is found in

Options

A. Internal ear
B. Kidney
C. Liver
D. Spleen.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where macula densa is located among the given options: internal ear, kidney, liver, or spleen.

2. **Identifying Macula Densa**: Macula densa is a specific structure that is known to be involved in the regulation of kidney function.

3. **Locating Macula Densa in the Kidney**: The macula densa is found in the nephron, which is the functional and structural unit of the kidney.

4. **Components of the Nephron**: The nephron consists of several parts, including:
- Glomerulus
- Proximal Convoluted Tubule (PCT)
- Loop of Henle
- Distal Convoluted Tubule (DCT)
- Collecting Duct

5. **Identifying the Location of Macula Densa**: The macula densa is specifically a thickening of the cells located in the distal convoluted tubule (DCT) of the nephron. It is situated where the DCT comes into contact with the afferent arteriole of the glomerulus.

6. **Conclusion**: Based on the above information, the correct answer to the question is that macula densa is found in the kidney.

**Final Answer**: Macula densa is found in the kidney.

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