1 Be clear in what you are claiming. 2  Tell the reader which claims are based on facts and which on values. 3  Provide good evidence in support of your claim. 4  If a connection between the evidence and the claim is not obvious, tell the reader the connection.
Gas Exchange Between Alveolar Spaces and Capillaries. The function of the respiratory system is to exchange two gases: oxygen and carbon dioxide. The exchange takes place in the millions of alveoli in the lungs and the capillaries that envelop them. As shown below, inhaled oxygen moves from the alveoli to the blood in the capillaries, and carbon dioxide moves from the blood in the capillaries to the air in the alveoli.
The air we breathe contains oxygen and other gases. Once in the lungs, oxygen is moved into the bloodstream and carried through your body. At each cell in your body, oxygen is exchanged for a waste gas called carbon dioxide.Your bloodstream then carries this waste gas back to the lungs where it is removed from the blood stream and then exhaled. Your lungs and respiratory system automatically perform this vital process, called gas exchange.In addition to gas exchange, your respiratory system performs other roles important to breathing.our lungs and respiratory system automatically perform this vital process, called gas exchange. In addition to gas exchange, your respiratory system performs other roles important to breathing.