Answers

2016-06-18T22:01:53+08:00
The main and primary function of the human Respiratory System is to receive oxygen (O) in order to continue living.
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2016-06-18T22:02:02+08:00
To take in oxygen and expel carbon dioxide as we breathe. The human respiratory system is a series of organs responsible for taking in oxygen and expelling carbon dioxide.
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