and intestines. The aorta later divides into the left and
right common iliacs, which supply the lower
extremities (fig. 1-35).
ARTERIES OF THE LOWER EXTREM-
ITIES.—The left and right common iliacs, upon
entering the thigh, become the femoral artery. At the
knee, this same vessel is named the popliteal artery
(fig. 1-35).
Venous System
Venous circulation is responsible for returning the
blood to the heart after exchanges of gases, nutrients,
and wastes have occurred between the blood and body
cells (fig. 1-36). To return this blood to the heart for
reoxygenation, the venous system begins with the
merging of capillaries into venules, venules into small
veins, and small veins into larger veins. The blood
vessel paths of the venous system are difficult to
1-29
HM3F0135C
LEFT
COMMON
CAROTID
LEFT
SUBCLAVIAN
PULMONARY
AXILLARY
BRACHIAL
LEFT
CORONARY
RADIAL
ULNAR
INTERNAL
CAROTID
EXTERNAL
CAROTID
RIGHT
COMMON
CAROTID
RIGHT
SUBCLAVIAN
INNOMINATE
ARCH OF
AORTA
RIGHT
CORONARY
AORTA
COMMON
ILIAC
EXTERNAL
ILIAC
FEMORAL
POPLITEAL
Figure 1-35.—Principal vessels of the arterial system.
