Question

Which of the following is a consequence for the formation of carboxyhaemoglobin in the blood?

• A. Inhalation of $CO$
• B. Inhalation of $C{O}_2$
• C. All of the above.
• D. Inhalation of $S{O}_2$

Answer 1

The correct option is A Inhalation of $CO$

Carbon monoxide is a poisonous gas released during the incomplete combustion of fossil fuels. It has greater affinity for haemoglobin than oxygen. When it is inhaled, $CO$ binds to haemoglobin to form carboxyhaemoglobin which is about 300 times more stable than the oxygen-haemoglobin complex. When the concentration of carboxyhaemoglobin reaches about 3–4 percent, the oxygen carrying capacity of blood is greatly reduced which may be fatal.
Hence option (b) is correct.