An Introduction to the Respiratory System

Functions of Respiratory System
• O 2 and CO 2 exchange between blood and air
• speech and other vocalizations
• sense of smell
• affects pH of body fluids by eliminating CO 2
• affects blood pressure by synthesis of
vasoconstrictor, angiotensin II
• breathing creates pressure gradients between
thorax and abdomen that promote the flow of
lymph and venous blood
• breath-holding helps expel abdominal
contents during urination, defecation, and
childbirth (Valsalva maneuver)