Question

Haemoglobin of the human blood forms a stable compound with which of the following gas, leads to death?

• A. Oxygen
• B. Carbon dioxide
• C. Carbon monoxide
• D. Nitrogen

Answer 1

The correct option is C Carbon monoxide

Carboxyhemoglobin or carboxyhaemoglobin (symbol COHb or HbCO) is a stable complex of carbon monoxide and hemoglobin (Hb) that forms in red blood cells upon contact with carbon monoxide (CO). Large quantities of CO hinder the ability of Hb to deliver oxygen to the body, because carboxyhemoglobin forms more readily than does oxyhemoglobin ($Hb{O}_2$).

Carbon monoxide binds to hemoglobin at the same sites as oxygen, but approximately 200 times more tightly.