Thirty seconds is not very long for red blood cells to circulate your entire body. Ahh. In that short amount of time the blood cell hits up the heart coming in on the right side, then head over to the lungs to get some much needed oxygen. Once oxygenated, it’s back to the heart, only it’s on the left side this time.
The heart shoots the cell rich with oxygen out into the body. As the blood is shot out it begins to drop off oxygen and pick up carbon dioxide. It’s like a taxi cab, postman and a garbage man at the same time.
Cells hold onto the carbon dioxide and take it with them back to the right side of the heart. The carbon dioxide is dropped off in the lungs and more oxygen is picked up. Then it’s time to start the journey all over again.
This continues for 100 days, which is the typical lifespan for a blood cell.