What does the circulatory system transport to body cells, and what does it carry away?

What does the circulatory system transport to body cells, and what does it carry away?

• A. Oxygen and nutrients to body cells; CO2 and metabolic wastes away from body cells
• B. Oxygen away from cells; nutrients to cells
• C. Carbon dioxide to cells; oxygen away
• D. Nutrients away; oxygen to cells

Answer: (A)

The circulatory system acts as a delivery and waste-removal network. It brings oxygen from the lungs and nutrients from the digestive system to body cells to support metabolism. At the same time, it picks up carbon dioxide produced by cells and other metabolic wastes to take them away for elimination—carbon dioxide to the lungs to be exhaled and wastes to the kidneys for excretion. This directional flow—O2 and nutrients to cells, CO2 and wastes away—best matches how the circulatory system functions in sustaining cellular activity and maintaining homeostasis.

The circulatory system acts as a delivery and waste-removal network. It brings oxygen from the lungs and nutrients from the digestive system to body cells to support metabolism. At the same time, it picks up carbon dioxide produced by cells and other metabolic wastes to take them away for elimination—carbon dioxide to the lungs to be exhaled and wastes to the kidneys for excretion. This directional flow—O2 and nutrients to cells, CO2 and wastes away—best matches how the circulatory system functions in sustaining cellular activity and maintaining homeostasis.