The function of the atrioventricular valves is to keep blood in the heart flowing in one direction, according to science educator Regina Bailey for About.com. These connect the atria and the ventricles together. They consist of endocardium and connective tissue. Atrioventricular valves are one of two types in the heart, the other being semilunar.Continue Reading
Atrioventricular valves can be further classified into the mitral valve and the tricuspid valve. According to LearnTheHeart.com, the mitral valve is more important in healthy heart function. When patients with recurring tricuspid valve endocarditis have the tricuspid valve removed, they are not likely to develop heart disease. Several diseases involve abnormalities of the mitral valve, including mitral valve prolapse, mitral regurgitation, tricuspid regurgitation and mitral stenosis.
Mitral valve prolapse is a disease of connective tissue causing the valves to prolapse into the left atrium during systole. This can lead to mitral regurgitation, which is the abnormal backflow of blood from the left ventricle to the atrium. Tricuspid regurgitation involves abnormal backflow of blood from the right ventricle to the right atrium. Mitral stenosis is a decrease in the mitral valve area that disrupts normal blood flow from the left atrium to the left ventricle. Tricuspid stenosis is a rare condition that may also develop from an abnormal mitral valve, notes LearnTheHeart.com. It involves abnormal stiffening or immobilization of the tissues of the tricuspid valve.Learn more about Human Anatomy
About.com suggests that blind spots have an explanation rather than a function. The explanation is that the part of the eye that the optic nerve exits from does not have rods or cones, thus resulting in a blind spot. Scholarpedia states that blind spots are present only in vertebrates because eyes in vertebrates develop from the brains, as compared to cephalopods, whose eyes develop from the skin and therefore have no blind spots.Full Answer >
The heart draws oxygenated blood from the lungs and distributes it to the rest of the body using a system of arteries and veins. Small coronary arteries and the pulmonary veins provide oxygenated blood into the heart. The pulmonary artery then pumps deoxygenated blood to the lungs where it is resupplied with oxygen.Full Answer >
Blood enters the heart in the right atrium, passes into the right ventricle and is then pumped to the lungs; after leaving the lungs, the blood travels back into the left atrium, into the left ventricle and then flows into the rest of the body. This is called the mammalian double-circulatory system because it has two distinct circuits. Keeping oxygenated blood completely separate from deoxygenated blood improves efficiency.Full Answer >
The function of the valves in the peripheral veins is to ensure that the overall movement of blood in the veins is in the right direction, toward the heart. This is especially important in the legs, where the blood must flow a relatively long distance against gravity.Full Answer >