The circulatory system is interesting for many reasons. The heart, arteries and veins are parts of the circulatory system.
The heart is made of 4 chambers, 2 atria and 2 ventricles. The right atria takes blood without oxygen gives it to the right ventricle which gives it to the lungs. The left atria takes it from the lungs through the rest of the body. The veins carry blood without oxygen to the heart. The arteries take pure blood from the heart and to the rest of the body. Blood is 55% plasma and 45% red blood cells, platelets and white blood cells. Red blood cells carry oxygen, white blood cells are part of the immune system, platelets clump together to stop bleeding and plasma is liquid and carries waste. All muscles have capillaries which are one atom thick and turn arteries to veins and veins to arteries. It has low blood pressure and oxygen goes in the tissues and carbon dioxide goes in the blood. Every heartbeat blood goes through the heart and the Aorta is the only artery that has carbon dioxide blood.
In conclusion the circulatory system is amazing.
By Jonathan Abraham