Blood flow refers to the movement of blood through the circulatory system, which includes the heart, arteries, veins, and capillaries. This process is essential for delivering oxygen and nutrients to cells while removing waste products. The heart acts as a pump, pushing blood through the arteries to various parts of the body. The flow of blood is regulated by factors such as blood pressure and vascular resistance. When the heart beats, it creates pressure that propels blood forward. As blood travels through smaller vessels, resistance increases, which can affect how efficiently blood circulates throughout the body.