How does the heart pump oxygenated blood around the body?

Blood that has been used up by the body (deoxygenated) enters the right side of the heart via a large vein known as the superior vena cava. It enters the right atrium from the top, which then contracts and pushes this blood through an atrioventricular valve known as the tricuspid valve (named this due to the 3 leaflets that make up the valve). The heart is full of valves, which make sure the blood only flows in one direction around the heart, i.e there is no back flow of blood. It then enters the lower, larger heart chamber known as the right ventricle, which then contracts and pushes blood through the pulmonary valve, into another vessel known as the pulmonary artery (pulmonary is a word that relates to the lungs, so this describes where the blood is going next) (this is the only artery in the body that transports deoxygenated blood). The blood then travels through this artery to the lungs, where it receives oxygen and therefore becomes oxygenated again. This oxygenated blood then travels from the lungs back to the heart through the pulmonary veins, into the left atrium. This left atrium contracts to push blood through the other atrioventricular valve known as the mitral valve (some textbooks may call this the bicuspid valve as only 2 leaflets make up this valve). It then enters the left ventricle, the largest heart chamber with the most muscle, as it has to pump blood to the whole of the body, including the arms and legs which are very far away. It does this by contracting and pushing the blood through the aortic valve, into a large artery known as the aorta which transports oxygenated blood to all the other arteries in the body. So in summary: Arteries carry oxygenated blood, and veins carry deoxygenated blood, EXCEPT in the pulmonary arteries and veins where this is reversed. The heart is made up of 4 chambers, the top smaller ones are atria, and the larger lower ones are ventricles There are valves between the chambers that prevent the back flow of blood Deoxygenated blood from the body --> pumped by the heart to the lungs --> oxygenated --> returns to heart to be pumped around the rest of the body