Answer: The air you breathe out has different amounts of oxygen, nitrogen, carbon dioxide and a few other substances in it than the air you breathed in. Your lungs absorb a lot of the oxygen, for example, which is then carried by red blood cells to your heart and muscles. Your body also produces carbon dioxide as a kind of waste product which is in the air you breathe out. So the air you breathe out has less oxygen but more carbon dioxide than the air you breathed in did. There are also other smaller changes that you could look up.
Answer: you breathe in something called oxygen and then breathe out something called carbon dioxide. Inside your body the oxygen gets running through your blood vessels ans heart and muscles. then even though you breathe in a bit of carbon dioxide- you breathe more out than in! :)
Answer: Breathing is an automatic muscular event, however there are breathing exercises that can be taught that will give you a more expansive inspiration and expiration. Dr. Andrew Weil has a breathing exercise CD that you can find. I found it helpful.
Breathing breathes in the atmosphere: not the whole atmosphereobviously, but its composition. Breathing in occursbecause of the necessity of oxygen-entrance and breathing outoccurs because of the necessity of carbon dioxide-exit.
The air consists of 79% nitrogen and 21% oxygen and 0.04% carbondioxide and equally tiny percentages of other gases. We breathe inthis 79% nitrogen and breathe out an equal percentage. We breathein 21% oxygen and breathe out 16% oxygen. We breathe in 0.04%carbon dioxide and breathe out 4-5% carbon dioxide.