Final answer:
The respiratory system exchanges oxygen and carbon dioxide via a two-part process involving ventilation and transport by the circulatory system. Oxygen is absorbed into the bloodstream in the lungs and transported to cells, while carbon dioxide is expelled from the body during exhalation.
Step-by-step explanation:
Respiratory System and Gas Exchange
The respiratory system is responsible for exchanging oxygen and carbon dioxide between the air we breathe and the body's cells. This process, known as respiration, involves two main stages: bringing oxygen into the body through the lungs and releasing carbon dioxide through exhalation. The circulatory system plays a critical role in transporting these gases between the lungs and body cells.
Ventilation and Oxygen Transport
The first process is ventilation, or breathing, which moves air to the lungs. Inside the lungs, the exchange of gases occurs at the level of the alveoli, where oxygen crosses the alveolar membrane to enter the bloodstream. The oxygen-rich blood is then carried to the body's tissues by the cardiovascular system.
Carbon Dioxide Removal
In tandem, carbon dioxide, a waste product of cellular respiration, diffuses from the blood into the alveoli, from where it is expelled during exhalation. This exchange is vital for maintaining the body's homeostasis and supporting cellular functions that rely on aerobic respiration to produce energy in the form of ATP.