Answers

2014-06-12T18:17:39+08:00
When you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. This increases the space in your chest cavity, into which your lungs expand.And when you breath out, or exhale, your diaphragm relaxes and moves upward into the chest cavity.The Intercostal muscles between the ribs also relax to reduce the space in the chest cavity.

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2014-06-12T18:20:09+08:00
Respiration or gas exchange takes place when you inhale and exhale

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