What is the role of capillaries in the circulatory system?

Capillaries play a crucial role in the circulatory system by connecting arteries and veins, forming an intricate network throughout the body's tissues. This network facilitates the exchange of nutrients, oxygen, carbon dioxide, and waste products between the blood and the cells. The walls of capillaries are thin, allowing substances to pass easily between the bloodstream and the surrounding tissues, which is essential for maintaining homeostasis and supporting cellular functions. Through this connection, capillaries ensure that oxygen-rich blood from arteries can deliver oxygen and nutrients to cells while also allowing carbon dioxide and metabolic wastes to be transported away for removal from the body to the veins. This function is fundamental to the overall efficiency and effectiveness of the circulatory system.