What does the circulatory system primarily rotate?

The circulatory system's primary function is to transport blood throughout the body. Blood is a vital fluid that carries various substances, including oxygen, nutrients, hormones, and waste products. As the heart pumps, blood flows through a network of arteries, veins, and capillaries, delivering oxygen to tissues and collecting carbon dioxide and other wastes for removal. This efficient transportation system is essential for maintaining homeostasis, supplying energy, and supporting cellular metabolism. While oxygen, food (nutrients), and carbon dioxide are all important components related to the circulatory system, they are carried by the blood rather than being the primary focus of what the system rotates. Therefore, recognizing that blood is the main substance circulated is key to understanding the role of the circulatory system.