2. The systemic circulation where the left side of the heart circulates oxygenated blood via the aorta and the major arteries to the rest of the body tissues.
Deoxygenated blood from the tissues collects into the large veins and is returned to the right side of the heart via the venae cavae.
The systemic side of the circulation functions at much higher pressures (80-120 mm Hg) than the pulmonary circulation.