Answer:
Blood circulation
Explanation:
The process being described is the circulation of blood.
Oxygen-rich blood leaves the heart through arteries and is transported to various cells and tissues where the exchange of oxygen for carbon dioxide takes place. Thereafter, the oxygen-deficient/carbon dioxide-rich blood moves into the veins and returns to the right side of the heart before traveling to the lung. In the lung, the carbon dioxide in the blood is exchanged for oxygen before the blood enters the left side of the heart and circulated all over again.
