Diaphragm
From Wikipedia, a free encyclopedia written in simple English for easy reading.
The diaphragm is a muscle that is at the bottom of the ribcage of mammals.
[edit] What it does
When breathing in, the diaphragm pulls down so that the size of the lungs increases. When breathing out, the diaphragm rests and goes up making a dome shape; decreasing the size of the lungs and pushing air out.
[edit] See also
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