Final answer:
The exchange of oxygen and carbon dioxide between the alveoli and the blood vessels is called external respiration.
Step-by-step explanation:
The process whereby the alveoli exchange oxygen for CO₂ with the blood vessels is known as external respiration. This process is essential for supplying oxygen to the body and removing carbon dioxide waste, thus maintaining homeostasis. During external respiration, oxygen diffuses from the alveoli into the blood where it binds to hemoglobin in the erythrocytes (red blood cells), and carbon dioxide diffuses in the opposite direction from the blood to the alveoli. This gas exchange process is driven by partial pressure differences, with oxygen entering the blood and carbon dioxide being expelled from the body.