Maintenance of the Body
and fourth processes also occur. As you can see, the respiratory and
circulatory systems are closely coupled, and if either system fails,
the body’s cells begin to die from oxygen starvation.
Te actual use of oxygen and production of carbon dioxide
by tissue cells, known as cellular respiration, is the cornerstone
of all energy-producing chemical reactions in the body. We dis-
, which is not a function of the respira-
tory system, in the metabolism section of Chapter 24.
Because it moves air, the respiratory system is also involved
with the sense of smell and with speech.
of the Respiratory System
Identify the organs forming the respiratory passageway(s)
in descending order until you reach the alveoli.
Describe the location, structure, and function of each of the
following: nose, paranasal sinuses, pharynx, and larynx.
List and describe several protective mechanisms of the
Te major function of the
is to supply the
body with oxygen and dispose of carbon dioxide. ±o accomplish
this function, at least four processes, collectively called
, must happen:
(commonly called breathing): Air
is moved into and out of the lungs (during
) so the gases there are continuously changed
Oxygen diﬀuses from the lungs to
the blood, and carbon dioxide diﬀuses from the blood to
Transport of respiratory gases:
Oxygen is transported
from the lungs to the tissue cells of the body, and carbon
dioxide is transported from the tissue cells to the lungs.
Te cardiovascular system accomplishes this transport us-
ing blood as the transporting ﬂuid.
Oxygen diﬀuses from blood to tissue
cells, and carbon dioxide diﬀuses from tissue cells to blood.
Te respiratory system is responsible for only the ﬁrst two pro-
, but it cannot accomplish its primary goal of
obtaining oxygen and eliminating carbon dioxide unless the third
The major respiratory organs in relation to surrounding structures.