ANATOMY AND PHYSIOLOGY OF THE RESPIRATORY SYSTEM
Section I. STRUCTURE AND FUNCTION OF THE RESPIRATORY ORGANS
a. Respiration. Respiration is the exchange of gases between the atmosphere
and the cells of the body. It is a physiological process. There are two types of
respiration: external respiration and internal respiration (figure 1-1). External
respiration is the exchange of gases between the air in the lungs and blood. Internal
respiration is the exchange of gases between the blood and the individual cells of the
Figure 1-1. Respiration.
b. Breathing. Breathing is the process that moves air into and out of the lungs.
It is a mechanical process. There are two types of breathing in humans: costal
(thoracic) breathing and diaphragmatic (abdominal) breathing (figure 1-2). In costal
breathing, the major structure causing the movement of air is the rib cage. In
diaphragmatic breathing, interaction between the diaphragm and the abdominal wall
causes air to move into and out of the lungs.
Figure 1-2. Breathing.