In the process of transport of `CO_(2)`, which phenomenon occurs between RBCs and plasma ?

Options

A. osmosis
B. adsorption
C. absorption
D. chloride shift

Answer

To answer the question regarding the phenomenon that occurs between red blood cells (RBCs) and plasma during the transport of carbon dioxide (CO₂), we can break down the process step by step.

### Step-by-Step Solution:

1. **Understanding CO₂ Transport**: The transport of carbon dioxide in the blood occurs primarily in three forms: dissolved in plasma, as bicarbonate ions (HCO₃⁻), and bound to hemoglobin. The focus here is on the bicarbonate ions.

2. **Formation of Bicarbonate Ions**: In the red blood cells, carbon dioxide reacts with water (H₂O) to form carbonic acid (H₂CO₃) through the action of the enzyme carbonic anhydrase. This carbonic acid then dissociates into bicarbonate ions (HCO₃⁻) and hydrogen ions (H⁺).

3. **Bicarbonate Ion Movement**: The bicarbonate ions (HCO₃⁻) produced in the RBCs need to be transported to the plasma. This movement occurs as bicarbonate ions diffuse from the RBCs into the plasma.

4. **Chloride Shift**: To maintain electrical neutrality and ionic balance during this exchange, chloride ions (Cl⁻) move from the plasma into the RBCs. This phenomenon is known as the "chloride shift" or "Hamburger phenomenon." It is crucial because it helps maintain the pH and ionic balance in the blood.

5. **Conclusion**: Therefore, the primary phenomenon occurring between RBCs and plasma during the transport of CO₂ is the chloride shift, where bicarbonate ions move out of the RBCs into the plasma while chloride ions move into the RBCs.

### Final Answer:
The phenomenon that occurs between RBCs and plasma in the transport of carbon dioxide is the **chloride shift**.

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