Systemic blood circulation, Arteries and Veins

This is a simplified diagram of how blood flows through your body.
From your heart, blood goes to the lungs (to get oxygenated, and to eliminate the CO2), then goes to the
HEAD, ARMS, LEGS, LIVER, SMALL Intestine, KIDNEYS and LEGS.
(Of course, it goes to all parts of your body, but this is a simplification).

CLICK the DIAGRAMS to get a LARGER VIEW.

Note the names of the major veins and arteries involved.(e.g., Carotid arteries and Jugular veins for the head).

Here is a comparison of the differences between ARTERIES and VEINS.
Note that Arteries ALWAYS carry blood away from the heart. They usually carry oxygenated blood, except in the case of the pulmonary artery.
Veins ALWAYS carry blood towards the heart. They usually have deoxygenated blood, except in the case of the pulmonary vein.

Detailed diagram of the cross-section of an artery and a vein.