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.
Confidence votes 315. De-oxygenated human blood is NOT blue. Blood in veins is NOT blue. Human blood is ALWAYS red regardless of whether it is venous or arterial blood, regardless of whether it is oxygenated or deoxygenated, regardless of whether it is inside the body or outside the body. Human blood is red. Period.