Which component is included in the circulatory system?

The heart is the central component of the circulatory system, which is responsible for pumping blood throughout the body. This blood transport is vital for delivering oxygen and nutrients to tissues while also facilitating the removal of waste products, like carbon dioxide. The heart works in conjunction with blood vessels, which include arteries, veins, and capillaries, to form a closed-loop system that ensures efficient circulation.

While the kidneys, brain, and lungs are essential organs with critical roles in the body, they do not directly constitute the circulatory system. The kidneys are part of the excretory system, involved in filtering blood and producing urine. The brain controls numerous body functions, including circulation, but it is not a component of the circulatory system itself. The lungs are part of the respiratory system, responsible for gas exchange but are not classified as a circulatory component. The heart remains the definitive component that actively propels blood and maintains the flow necessary for circulation.