Question

True or false large veins, medium veins, and venules have valves to prevent the backflow of blood.

Answer 1

Large veins, medium veins, and venules have valves to prevent the backflow of blood.

Step-by-step explanation:

True. Large veins, medium veins, and venules have valves to prevent the backflow of blood. This is because veins are low-pressure vessels and the valves help to promote the unidirectional flow of blood toward the heart and prevent backflow caused by the inherent low blood pressure in veins as well as the pull of gravity.

Answer 2

True, large veins, medium veins, and venules have valves to prevent the backflow of blood.

Step-by-step explanation:

True, large veins, medium veins, and venules have valves to prevent the backflow of blood. Veins are thin-walled vessels with large and irregular lumens. These low-pressure vessels rely on valves to promote the unidirectional flow of blood toward the heart and prevent backflow caused by low blood pressure and gravity.