Chloride shift is essential for the transport of

Options

A. `O_(2)`
B. `CO_(2)`
C. `CO`
D. `O_(3)`

Answer

**Step-by-Step Solution:**

1. **Understanding Chloride Shift**: The chloride shift, also known as the Hamburger phenomenon, is a physiological process that occurs in the cardiovascular system, specifically in red blood cells (RBCs).

2. **Role of Carbon Dioxide**: The process begins with carbon dioxide (CO2) produced in the tissues. This CO2 diffuses into the red blood cells.

3. **Formation of Bicarbonate**: Inside the RBCs, CO2 reacts with water (H2O) in the presence of the enzyme carbonic anhydrase, leading to the formation of bicarbonate ions (HCO3-) and hydrogen ions (H+). This reaction can be represented as:
\[ CO2 + H2O \rightleftharpoons H2CO3 \rightleftharpoons HCO3^- + H^+ \]

4. **Exchange of Ions**: Once bicarbonate ions are formed, they move out of the RBCs into the plasma. To maintain electrical neutrality, chloride ions (Cl-) from the plasma enter the RBCs. This exchange of bicarbonate and chloride ions is what is referred to as the chloride shift.

5. **Conclusion**: The entire process is crucial for the transport of carbon dioxide from the tissues to the lungs, where it can be exhaled. Therefore, the chloride shift is essential for the transport of carbon dioxide.

**Final Answer**: The chloride shift is essential for the transport of **carbon dioxide (Option B)**.

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