The primary functions of the respiratory system are to bring oxygen into the lungs, transfer the oxygen to the blood, and expel the waste product called carbon dioxide.
(The primary functions of the respiratory system; are; to bring oxygen into the lungs, transfer the oxygen to the blood, and expel the waste product) (the waste product; called; carbon dioxide)
The primary functions of the respiratory system the waste product
are called
to bring oxygen into the lungs, transfer the oxygen to the blood, and expel the waste product
carbon dioxide