COMEDK2021ChemistryEnvironmental Chemistry
Carbon monoxide is poisonous to human beings because
Options
- Ait binds 300 times more strongly to haemoglobin than oxygen.
- Bit doesn't bind to haemoglobin
- Cit forms cyanide in body.
- Dit leads to coagulation of blood.
Correct answer
A. it binds 300 times more strongly to haemoglobin than oxygen.
Step-by-step solution
Carbon monoxide ( CO ) has a very high affinity for haemoglobin, which is approximately 300 times greater than that of oxygen ( O₂ ). When CO is inhaled, it binds to the iron atom in the haemoglobin molecule to form carboxyhaemoglobin, which is much more stable than oxyhaemoglobin. This binding prevents haemoglobin from transporting oxygen to the tissues, leading to oxygen deprivation and toxicity. Answer: it binds 300 times more strongly to haemoglobin than oxygen.