APPLIED RADIOLOGICAL ANATOMY

Detailed explanation-1: -Gas 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.

Detailed explanation-2: -Once the venous blood returns to the lungs, the carbon dioxide diffuses out of the bloodstream, through the capillaries, and into the alveoli from where it is expelled, during which time oxygen simultaneously binds with hemoglobin to be carried back to the tissues.

Detailed explanation-3: -This exchange of oxygen and carbon dioxide is called respiration.

Detailed explanation-4: -Your lungs excrete carbon dioxide as you breathe out, your kidneys filter out nasties to produce urine, removing nitrogen waste from your body, and your skin sheds excess salt through sweat.