Exposure to carbon monoxide ( from coal gas ) is extremely dangerous and can kill a patient because

Options

A. The compound carboxy-hemoglobin is formed with hemoglobin which can gradually clot the blood resulting in circulatory failure.
B. Caboxy-hemoglobin reduces the ability of blood to transport oxygen by rupturing a vast majority of erythrocyte.
C. Carboxy-hemoglobin greatly modifies the structure of hemoglobin, thus making it lose its affinity for oxygen.
D. The compound formed, carboxy-hemoglobin does not allow RBCs to act for their respiratory function.

Answer

**Step-by-Step Solution:**

1. **Understanding Carbon Monoxide (CO):** Carbon monoxide is a colorless, odorless gas that is produced from burning fossil fuels, including coal gas. It is highly toxic to humans and can lead to poisoning.

2. **Mechanism of Action:** The primary reason CO is dangerous is due to its ability to bind to hemoglobin in red blood cells (RBCs). Hemoglobin is responsible for transporting oxygen from the lungs to the rest of the body.

3. **Affinity for Hemoglobin:** Carbon monoxide has a much higher affinity for hemoglobin compared to oxygen—approximately 200 times greater. This means that when CO is present, it will preferentially bind to hemoglobin over oxygen.

4. **Formation of Carboxyhemoglobin:** When CO binds to hemoglobin, it forms a stable compound known as carboxyhemoglobin. This compound does not easily dissociate, meaning that once CO is bound, it effectively blocks the binding sites for oxygen.

5. **Impact on Oxygen Transport:** As a result of carboxyhemoglobin formation, the hemoglobin is unable to transport oxygen. This leads to a decrease in the amount of oxygen available to tissues and organs, which can cause serious health effects and potentially lead to death.

6. **Conclusion:** Therefore, exposure to carbon monoxide is extremely dangerous because it prevents red blood cells from performing their essential function of oxygen transport, leading to hypoxia (lack of oxygen) in the body.

**Final Answer:** Exposure to carbon monoxide from coal gas is extremely dangerous and can kill a patient because the compound formed (carboxyhemoglobin) does not allow the RBCs to perform their respiratory function effectively.

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