Answer:
They ensure blood flows in one direction throughout the heart
Step-by-step explanation:
The heart has 4 valves namely;
- The mitral and tricuspid valves which control the flow of blood from the atria to the ventricles
- The pulmonary and aortic valves which control the flow of blood out of the ventricles.
When blood passes through the valve, the valve prevents the back flow of the blood as the muscles of the heart contracts and relaxes.