The cardiovascular system is a vast and complex system of the heart, blood, lungs, and blood vessels. They are all connected though which is an awesome concept about our human body! When blood is made in the bone marrow, it is sent through veins to get pumped through the heart and into the lungs (heart beat). When the blood is being pushed through the blood vessels they are pushing on the walls trying to move throughout the system (blood pressure). When the oxygenated blood (Red blood cells) get through the heart, they are then sent to capillaries of the different tissues where they release their oxygen and are then sent back to the heart always in the plasma as well (plasma and functions of blood). If they go through too many cycles, they are then eaten up by the leukocytes (white blood cells). When the heart gets filled with blood, it's made sure by the outer layers, that it isn't shocked or infected by other organs in the body (coverings of heart and heart wall). There are always complications though, and blood can be lost. When it is, you must make sure you get the best treatment by getting the right blood transfused back into your body, or else you wouldn't have done anything to help yourself (blood and blood types).
How does everything connect?
The heart and blood has been explained individually, but what do they do together that lets them make what we call the cardiovascular system?