Question

‘X’ is poisonous gas, which is produced on incomplete burning of fossil fuels such as coal and petroleum. In our blood, haemoglobin binds with ‘X’ to form ‘Y’. Here, X and Y are respectively.

• A. Sulphur dioxide and chlorofluorocarbons
• B. Carbon dioxide and carbaminohaemoglobin
• C. Nitrogen oxide and carbaminohaemoglobin
• D. Carbon monoxide and carboxyhaemoglobin

Answer 1

The correct option is D Carbon monoxide and carboxyhaemoglobin

Carbon monoxide is a poisonous gas that is released from the automobile exhaust when the fuel is not burnt completely. This gas binds with the haemoglobin present in the blood as haemoglobin has more affinity towards carbon monoxide than oxygen and thus reduces the oxygen binding capacity of blood. It binds with haemoglobin to form carboxyhaemoglobin. Thus, X is carbon monoxide and Y is carboxyhaemoglobin.