Which enzyme is present in RBCs and plasma to
catalyse the given reaction?
`CO_(2)+H_(2)O hArr underset ("Carbonic acid")(H_(2)CO_(3)) hArr H^(+)+ HCO_(3)^(-)`

Options

A. Carbonic anhydrase
B. Catalase
C. Aldolase
D. Carboxylase

Answer

To answer the question regarding which enzyme is present in red blood cells (RBCs) and plasma to catalyze the reaction between carbon dioxide (CO2) and water (H2O) to form carbonic acid (H2CO3), which subsequently dissociates into hydrogen ions (H+) and bicarbonate ions (HCO3^-), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reaction**:
The reaction in question is:
\[ CO_2 + H_2O \rightleftharpoons H_2CO_3 \rightleftharpoons H^+ + HCO_3^- \]
This reaction involves the conversion of carbon dioxide and water into carbonic acid, which can further dissociate into hydrogen ions and bicarbonate ions.

2. **Understand the Role of Enzymes**:
Enzymes are biological catalysts that speed up chemical reactions in the body. In this case, we need to find out which enzyme facilitates the conversion of CO2 and H2O into H2CO3.

3. **Identify the Enzyme**:
The enzyme that catalyzes this reaction is **carbonic anhydrase**. This enzyme is crucial in the respiratory process as it helps in the rapid conversion of carbon dioxide and water into carbonic acid.

4. **Location of the Enzyme**:
Carbonic anhydrase is found in both red blood cells (RBCs) and plasma. This allows for efficient transport and conversion of CO2 in the blood.

5. **Conclusion**:
Therefore, the enzyme present in RBCs and plasma that catalyzes the given reaction is **carbonic anhydrase**.

### Final Answer:
The enzyme present in RBCs and plasma to catalyze the reaction is **carbonic anhydrase**.

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