Final answer:
The term that best defines the exchange of air between the lungs and ambient air, also known as breathing, is ventilation. Ventilation is the physical movement of air to and from the lungs, which is the first step in the process of respiration, a larger function of the respiratory system to exchange gases with the circulatory system.
Step-by-step explanation:
The term that best defines the exchange of air between the lungs and ambient air, which we commonly refer to as breathing, is ventilation. Breathing, or respiration, is the process of moving air in and out of the lungs, where gas exchange takes place between blood and air. This exchange involves two main processes: ventilation, the physical movement of air to and from the lungs, and the biochemical gas exchange, which occurs in the lungs where oxygen diffuses from the air into the blood while carbon dioxide diffuses from the blood into the air.
Ventilation starts the respiration process, but it is also part of the larger respiratory system's function, which includes the transfer of oxygen to, and the removal of carbon dioxide from, the circulatory system. Oxygenated blood is carried from the lungs to tissues throughout the body, and the exchange of gases between the blood and body cells occurs at the capillary level, supporting cellular functions and maintaining homeostasis.