The blood pumped by our heart 100,000 times a day circulates through these chambers, passing through opening and closing doors; in other words, (valves). Our heart has four chambers, two small and two large. In response to the question, "How many heart valves are there?", the following can be said. The small chambers in the heart are called atria, and the large chambers are called ventricles. The chambers on the left side carry oxygenated blood, while those on the right side carry deoxygenated blood to the lungs. The door between the small and large chambers on the left side of our heart is called the mitral valve, and the door through which blood from the large chamber is pumped to the whole body is called the aortic valve. The door between the small and large chambers on the right side is called the tricuspid valve, and the door through which blood from the large chamber on the right side passes to the lungs to be oxygenated is called the pulmonary valve.