CHAPTER 37 – THE CIRCULATORY AND RESPIRATORY SYSTEMS

circulatory system. is responsible for the movement of substances (O. 2, CO 2, nutrients, & wastes) through the body. The human circulatory system has three components: the heart, the . blood. vessels, and the . blood. THE HEART. The function of the heart is to keep the blood moving constantly in the body. The heart is a large organ made of cardiac. muscle. cells ................
................