Refer to the given schematic representation of circulation in humans. ldentify X, Y and Z and select the correct statement regarding them.

Options

A. In the absence of Z in body, nutrient uptake by body cells will remain unaffected but elimination of waste from body cells will not take place.
B. Y has no valves while X has valves to prevent backward flow of blood.
C. X is vena cava that carries deoxygenated blood from body parts to the left atrium of heart.
D. Through Y, the medicines reach the heart from where they are pumped all over the body.

Answer

B

Explanation

In the given figure X refers to systemic vein that supply deoxygenated blood from X the body tissues to the heart. Y refers to systemic artery that supply oxygenated blood to the tissues from heart. Z is capillaries. Main function of capillaries is exchange of nutrient and waste between the blood and tissue cells through interstitial fluid.