The Heart - Circulatory System

The video explains the human heartbeat and its continuous nature, highlighting the heart as a strong muscle that pumps blood throughout the body. It describes the heart's structure, including its two sides and their functions. The video also covers the role of blood vessels, such as arteries and capillaries, in transporting oxygenated blood to cells and returning carbon dioxide-rich blood to the heart. The circulatory system is introduced, emphasizing the heart's automatic beating and its frequency over a lifetime.

Explain the process of how blood returns to the heart after circulating through the body.

What happens to carbon dioxide in the blood during respiration?