Question

If man inhales a normal concentration of oxygen but also the same concentration of CO; he suffers from suffocation because
A. CO reacts with oxygen which is thus removed from the air reaching the lungs.
B. CO reacts faster with hemoglobin and products cannot dissociate.
C. CO affects the diaphragm and intercostal muscles.
D. CO affects vagus nerves.

Answer 1

Hint: Carbon monoxide (CO) has almost 210 times higher affinity with hemoglobin than O$_2$. The CO and hemoglobin form a stable compound after their reaction.

Complete answer: The affinity of CO and hemoglobin is much higher than oxygen and hemoglobin.
So, when a man inhales a normal concentration of oxygen and also the same concentration of CO; he suffers from suffocation because after the reaction of CO with hemoglobin stable compound is formed which cannot dissociate into the blood.
This stable compound inhibits oxygen to bind with hemoglobin, as a result, the oxygen level in the blood is reduced, and the level of carbon dioxide increases.
Carbon monoxide also diminishes oxygen delivery to all of the tissues of the body which is very poisonous when CO levels get high in the blood.
This results in suffocation and even death.

So, the correct answer is option B. Carbon monoxide (CO) reacts faster with hemoglobin and products cannot dissociate.

Note: Ozone, carbon monoxide, particulate matter, sulfur dioxide, etc. are the major air pollutant gases that are present in the atmosphere. Oxygen binds with hemoglobin and forms oxyhemoglobin that passes oxygen to all the tissues and on the tissues carbon dioxide binds to hemoglobin to form carboxyhemoglobin which releases carbon dioxide on the lungs.