Question

How much greater affinity carbon monoxide has for haemoglobin as compared to oxygen?

• A. 1000 times
• B. 200 times
• C. 20 times
• D. 2 times

Answer 1

The correct option is B 200 times

Carbon monoxide is a harmful gas, that combines with haemoglobin to form a stable compound. It displaces the oxygen that is normally carried by the haemoglobin and reduces the oxygen-carrying ability of the blood. Carbon monoxide may be produced by the incomplete burning of various fuels, such as gasoline, coal, wood, and other carbon-containing materials. It also occurs in automobile exhaust fumes and in cigarette smoke. The affinity between hemoglobin and carbon monoxide is approximately 200 times stronger than the affinity between hemoglobin and oxygen, so hemoglobin binds to carbon monoxide in preference to oxygen.