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

A person never dies from carbon monoxide poisoning. Carbon monoxide doesn’t act as a poison in the body rather it starves/suffocates the tissues. The tissues get deprived of oxygen.

Complete answer:
Carbon monoxide has more than 200 times greater affinity for haemoglobin than oxygen. Carbon monoxide combines with haemoglobin far more readily than oxygen, forming a relatively stable compound i.e. carboxyhemoglobin. Carbon monoxide combines with haemoglobin to make a compound i.e. carboxyhemoglobin (Hb and CO) which are difficult to separate. So the amount of haemoglobin for oxygen in the blood is decreased. This starves the tissues of oxygen. So death occurs due to tissue suffocation and not from poisoning.

CO combines with haemoglobin 210 times more rapidly than oxygen. It occurs due to coal burning in a closed room. The oxygen–haemoglobin dissociation curve, also called the oxyhaemoglobin dissociation curve or oxygen dissociation curve (ODC), is a curve that plots the proportion of haemoglobin in its saturated oxygen form on the vertical axis against the prevailing oxygen tension on the horizontal axis.

This curve is an important tool for understanding how our blood carries and releases oxygen. Specifically, the oxyhaemoglobin dissociation curve relates oxygen saturation $(SO_2)$ and partial pressure of oxygen in the blood $(PO_2)$, and is determined by what is called haemoglobin affinity for oxygen"; that is, how readily haemoglobin acquires and releases oxygen molecules into the fluid that surrounds it. The shift in these curves tells us about the changes in the gaseous environment of our body.

Note: Breathing pure oxygen. In the emergency room, you may breathe pure oxygen through a mask placed over your nose and mouth. This helps oxygen reach your organs and tissues. If you can't breathe on your own, a machine (ventilator) may do the breathing for you. Spending time in a pressurized oxygen chamber. In many cases, hyperbaric oxygen therapy is recommended. This therapy involves breathing pure oxygen in a chamber in which the air pressure is about two to three times higher than normal. This speeds the replacement of carbon monoxide with oxygen in your blood.