Blood carries `CO_(2)` mainly in which form ?

Options

A. Hb `CO_(2)`
B. Physical solution form
C. Carbonic acid
D. Carboxy hemoglobin

Answer

To answer the question "Blood carries CO₂ mainly in which form?", we can break down the information provided in the transcript into a step-by-step solution.

### Step-by-Step Solution:

1. **Understanding CO₂ Transport in Blood**: Blood transports carbon dioxide (CO₂) in three main forms:
- As carbamino compounds (attached to hemoglobin)
- As dissolved gas in plasma
- As bicarbonate ions (HCO₃⁻)

2. **Identifying the Forms**:
- **Carbaminohemoglobin (HbCO₂)**: This is when CO₂ binds to hemoglobin, accounting for about 20-25% of CO₂ transport.
- **Physical Solution Form**: This refers to CO₂ dissolved directly in the plasma, which constitutes about 7% of CO₂ transport.
- **Carbonic Acid (Bicarbonate)**: This is the form in which the majority of CO₂ is transported, approximately 70% of CO₂ in the blood is in this form.

3. **Analyzing the Options**:
- **Option 1: HbCO₂ (Carbaminohemoglobin)** - 20-25%
- **Option 2: Physical Solution Form** - 7%
- **Option 3: Carbonic Acid (Bicarbonate)** - 70%
- **Option 4: Carboxyhemoglobin** - This is not a form of CO₂ transport but occurs when carbon monoxide binds to hemoglobin.

4. **Conclusion**: Since the question asks for the main form in which blood carries CO₂, we can conclude that the majority of CO₂ is transported as bicarbonate ions (Carbonic Acid), which accounts for about 70% of CO₂ in the blood.

### Final Answer:
Blood carries CO₂ mainly in the form of **Carbonic Acid (Bicarbonate)**.

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