Right-click the picture you want to change. Click Format Picture. In the Format Picture dialog box, click the Picture tab. Under Image control, click Washout in the Color list, and then click Recolor.
There are three major types of blood vessels: the arteries, which carry the blood away from the heart; the capillaries, which enable the actual exchange of water and chemicals between the blood and the tissues; and the veins, which carry blood from the capillaries back toward the heart.
Arteries carry blood away from the heart, while veins carry blood towards the heart. Capillaries carry blood from arteries to veins. Arteries generally carry oxygenated blood from the heart to the tissues and organs during the systolic heartbeat cycle. They are under high pressure. (the only exception is the pulmonary arteries which carries deoxygenated blood from the heart to the lungs).