ANATOMY

Detailed explanation-1: -So, the correct option is ‘Veins’.

Detailed explanation-2: -Veins have valves to prevent the backflow of blood because the blood in veins flow .

Detailed explanation-3: -Many veins, particularly those in the arms and legs, have one-way valves. Each valve consists of two flaps (cusps or leaflets) with edges that meet. Blood flowing toward the heart pushes the flaps open like a pair of one-way swinging doors.

Detailed explanation-4: -The valves open, allowing the blood to flow, and close, stopping the blood from flowing backwards. After running through this network of veins, blood reaches the heart and travels to the lungs, which supply it with oxygen and allow it to expel carbon dioxide and other waste.

Detailed explanation-5: -Similar to the valves associated with the heart, yet dissimilar from the arteries, veins contain valves to ensure that the blood flows in only one direction, toward the heart. (Arteries don’t require valves because pressure from the heart is so strong that blood is only able to flow in one direction.)