Gas exchange occurs by the process of what in the respiratory system

It occurs by the process of breathing! The diaphragm expands and allows air into the lungs. This air is carries into your wind pipe, and in the tiny air sacs called aveiolli that are in your lungs. These aveiolli are connected to capillaries that then send carbon dioxide out throw the wind pipe yet again, and also spread the oxygen collected throughout the body.

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