Gases as a law exist independently of each other
Gases move rapidly and randomly
So in the alveoli (lungs air bags) we have "fresh" air entering this has Approx 80% Nitrogen 19%oxygen and a little carbon-di-oxide and other gases.
In our blood we have high carbon-di-oxide levels in the air we have low carbon-di-oxide levels and vice versa for oxygen
If you have smelled perfume and noticed that you can smell it from far away that's a result of diffusion.
Effectively the respiratory gases diffuse to equalize in concentration in both the blood and in alveoli. Basically in blood (deoxygenated) CO2 concentration is 50 mmHg in the air sacs it is 45 mmHg so they try t equalize.
This results in carbon-di-oxide leaving the blood and entering the alveoli.
The same thing happens to the oxygen. It's higher in air than in blood so the oxygen moves from high concentration (in air) to low concentration (in blood)
The end result is carbbon-di-oxide leaving blood and oxygen entering blood this is a basic!!! overview of the gas exchange.
Easiest answer: Capillary
The actual sites of gas exchange within the lungs are the alvioli.
The gas exchange that takes place in the lungs are carbon dioxide and oxygen.
The efficiency of gas exchange in the lungs of vertebrates is greater because it increases the lungs' internal surface area.
via their lungs
gaseous exchange
The gas exchange that takes place in the lungs are carbon dioxide and oxygen.
Oh
alveoli
suffocation
lungs
Gas exchange.
greatest area for gas exchange in the lungs is provided by Whoever wrote the above answer is a dick head. Try ALVEOLI.