Breathing is moving 1 in and out of the 2 . The air in and out is called 3 .
If a 4 cannot breathe, they will 5 .
Gas 6 in Humans.
7 and carbon 8 switch places between a 9 (part of the bloodstream) and an 10 (an air 11 in the lungs).
Breathing helps people do 12 very important things:
1. Get oxygen into the body. Every part of the 13 needs oxygen to survive.
The 14 way humans can get oxygen is to breathe it in.
2. Get 15 dioxide 16 of the body. When the body makes 17 ,
18 gets left over.
The body needs to get rid of extra carbon dioxide, because too much of it is 19 .
The only way humans can get rid of carbon dioxide is to 20 it out.