How does the lungs know which is O2 and CO2? We breathe a ton of different gasses daily but what happens to the other gases other than O2 and CO2 when inhaled?

Question

How does the lungs know which is O2 and CO2? We breathe a ton of different gasses daily but what happens to the other gases other than O2 and CO2 when inhaled?

In: 729

Answer 1

The CO2 molecule is 50% larger. They are not hard to tell apart!

But CO (carbon monoxide) is very close in size to O2 which is a huge problem. Not only can it displace oxygen in the air like CO2 does, it can *replace* oxygen in your blood stream. So, it’s doubly bad.