Final answer:
The mitral valve directs blood flow from the left atrium to the left ventricle in the heart, and it prevents the backflow of blood during ventricular contraction.
Step-by-step explanation:
The valve that directs blood flow from the left atrium to the left ventricle is the mitral valve, also known as the bicuspid valve or the left atrioventricular valve. This valve has two cusps, the anterior medial cusp and the posterior medial cusp and its function is crucial for the proper flow of blood through the heart. When the mitral valve opens, it permits blood to move from the left atrium into the left ventricle, while preventing the backflow of blood from the ventricle to the atrium during ventricular contraction.