What is use of carbondioxide?

Answer 1

Carbondioxide or (Co2) is a Gas that we cannot live without. Without Carbondioxide, plants couldn't breathe, meaning that oxygen would not be produced ending up in obvious death. You see, we breathe in Nitrogen, Oxygen and Hydrogen (we also breathe other gases like Helium) and Carbondioxide. The body DOES NOT need Co2 directly, therefore the lungs emit the Co2 from our bodies. We breathe it out into the Biosphere and Atmosphere, then trees and plants breathe it in. Then they breathe out Oxygen; the cycle goes on forever. Too much Co2 however is what we don't need.