The heart is a vital organ that pumps blood around the body. The heart is a curtail part of your body because it help us humans survive. this is because without the heart you would not have any blood and you will stop breathing. The heart carry the oxygen around the body which, helps us breath. Then the lungs will relies the carbon dioxide. The average amount of heartbeats is about 100,000 times which means in your life your heartbeats over 2.5 million times. Your heart is the same size as your fist clench.
The human circulatory system is made up of the heart, blood vessels and the lung. Without this we would die as soon as we were born. Every part of our body is important and we need. blood is red and veins. The heart goes first right atrium, then the tricuspid valve (like a door way that only open one way). (otherwise the oxygen and carbon dioxide go together and then you might die) then the right ventricle finally up the pulmonary valve. The returning blood cells the first left atrium then through then through the left ventricle the to the aortic valve. When you breath in oxygen then it goes to your lungs and then you breath carbon doxiade out.