Carbonic anhydrase is present in very high concentration in

Options

A. plasma
B. epithelial tissue
C. RBC
D. muscular tissue

Answer

**Step-by-Step Solution:**

1. **Understanding Carbonic Anhydrase**: Carbonic anhydrase is an enzyme that catalyzes the conversion of carbon dioxide and water to bicarbonate and protons. This reaction is crucial for maintaining acid-base balance in the body and facilitating gas exchange in tissues.

2. **Identifying the Locations**: The question asks where carbonic anhydrase is present in very high concentration. The options provided are plasma, epithelial tissues, red blood cells (RBCs), and muscular tissue.

3. **Analyzing Each Option**:
- **Plasma**: While plasma does contain some enzymes, the concentration of carbonic anhydrase is relatively low compared to other locations.
- **Epithelial Tissues**: These tissues are involved in absorption and secretion but do not have a particularly high concentration of carbonic anhydrase.
- **Muscular Tissue**: Muscles have various enzymes for energy metabolism, but carbonic anhydrase is not highly concentrated here.
- **Red Blood Cells (RBCs)**: RBCs are specifically designed for gas transport and have a very high concentration of carbonic anhydrase to facilitate the rapid conversion of carbon dioxide to bicarbonate, which is essential for transporting CO2 from tissues to the lungs.

4. **Conclusion**: Based on the analysis, the highest concentration of carbonic anhydrase is found in red blood cells (RBCs).

5. **Final Answer**: Therefore, the correct answer is **RBCs (Red Blood Cells)**.

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