WASHINGTON, DC - JANUARY 20: U.S. President Donald Trump delivers his inaugural address on the West Front of the U.S. Capitol on January 20, 2017 in Washington, DC. In today's inauguration ceremony Donald J. Trump becomes the 45th president of the United States.
One-Way Valves in the Veins. One-way valves consist of two flaps (cusps or leaflets) with edges that meet. These valves help veins return blood to the heart. As blood moves toward the heart, it pushes the cusps open like a pair of one-way swinging doors (shown on the left).
Varicose Veins. Varicose veins are dilated tortuous veins with weakened walls and valves that no longer close when they should. They occur in the lower extremities and are important for the health of the skin and superficial tissues. They appear as bulges under the skin of the erect individual and disappear when the limb is elevated above the heart.