Valves?
Capillaries
a valve
Flaps of tissue that force unidirectional flow are called valves.
They are called valves, or leaflet valves in the veins, that interlock to prevent backflow of the blood.
Both types of semilunar valve, aortic and pulmonary, have three cusps. These flaps make sure that blood only flows in one direction.
These are valves, and are found in veins to prevent blood from flowing backwards.
valves
Valves. Mitral and aortic.
In veins, there are valves that prevent back flow. <><><><><> There are also valves in the heart to force the blood to go in one direction only when the heart contracts.
Heart valves, specifically atrioventricular and semilunar valves, prevent the backflow of blood and help it flow in one direction through the heart. The valves open and close in response to pressure changes during the cardiac cycle.
cusps
Valves