Does anybody know what and how much of each element we breathe in, and how much we breathe out? Also, is this the same for plants as it is for humans?

harish_256

I'd assume that the amount of each element we breathe in would be similar to the amount in which they are present in our atmosphere, which would mean 78% of it is nitrogen, 21% is oxygen, 0.9% is argon, and so on... When we exhale, however, we probably let out a lot less molecular oxygen and a lot more carbon dioxide (in the form of carbon + oxygen). Plants on the other hand, would exhale a lot more molecular oxygen... Oct 11 03, 6:46 AM

Gnomon

We breathe in 78% Nitrogen, 21% Oxygen and 1% a few other things. We breathe out 78% Nitrogen, 20% Oxygen, 1% Carbon Dioxide and 1% other stuff. Plants are different: they have two different functions: their breathing is exactly the same as ours, and they do it 24 hours a day, but during the day, they also feed on the air, which turns carbon dioxide into oxygen. I'm afraid I don't know the quantities. The net result for plants is that they give out more oxygen than they take in. Oct 11 03, 3:49 PM