This is incorrect. While valves are present in veins to prevent backward flow, these are not semilunar valves. The valves in veins are simply known as venous valves. They help ensure one-way blood flow back to the heart, particularly from lower extremities, but they are not classified as semilunar valves. Semilunar valves are found only at the exits of the heart's ventricles.
Arteries do not have semilunar valves.
Capillaries do not have semilunar valves.
his is the correct statement. The semilunar valves are located at the base of the aorta (aortic valve) and the pulmonary artery (pulmonary valve). These valves prevent the backflow of blood into the ventricles after it has been pumped out of the heart. When the ventricles relax, the semilunar valves close, ensuring that blood does not flow backward from the arteries into the heart.
his is the correct statement. The semilunar valves are located at the base of the aorta (aortic valve) and the pulmonary artery (pulmonary valve). These valves prevent the backflow of blood into the ventricles after it has been pumped out of the heart. When the ventricles relax, the semilunar valves close, ensuring that blood does not flow backward from the arteries into the heart.