What is the function of the mitral valve in the heart?

The mitral valve serves a critical role in the heart's anatomy and function by separating the left atrium from the left ventricle. During the cardiac cycle, when the left atrium fills with oxygen-rich blood from the lungs, the mitral valve opens to allow that blood to flow into the left ventricle. When the ventricle contracts to pump blood out to the aorta, the mitral valve closes, preventing any backflow into the atrium. This valve is vital for maintaining efficient blood circulation throughout the body by ensuring that blood flows in the correct direction, specifically from the atrium into the ventricle and not the other way around.