Anatomy & Physiology I and II

Anatomy & Physiology Study Guide emerges on the anterior, medial surface of the thigh as the femoral artery. Roughly 5 cm (2 in.) distal to the emergence of the femoral artery , the deep femoral artery branches off its lateral surface. The deep femoral artery, which gives rise to the femoral circumflex arteries, supplies blood to the ventral and lateral regions of the skin and deep muscles of the thigh. The femoral artery continues inferiorly and posterior to the femur. As it approaches the knee, it gives rise to the descending genicular artery, which supplies the area around the knee. At the popliteal fossa, posterior to the knee joint, the femoral artery becomes the popliteal artery , which then branches to form the posterior and anterior tibial arteries. The posterior tibial artery gives rise to the fibular artery, or peroneal (perone, fibula) artery, before continuing inferiorly along the posterior surface of the tibia. The anterior tibial artery travels between the tibia and fibula, coming out on the anterior surface of the tibia. As it moves downward toward the foot, the anterior tibial artery provides blood to the skin and muscles of the anterior portion of the leg. Arteries of the Foot When it reaches the ankle, the anterior tibial artery becomes the dorsalis pedis artery, which then branches repeatedly, supplying the ankle and dorsal portion of the foot. As it reaches the ankle, the posterior tibial artery divides to form the medial and lateral plantar arteries, which supply blood to the plantar surface of the foot. These arteries are connected to the dorsalis pedis artery through a pair of anastomoses. The arrangement produces a dorsal arch and a plantar arch; small arteries branching off these arches supply the distal portions of the foot and the toes. 20.12 Systemic Veins The Superior Vena Cava All the body’s systemic veins (except the cardiac veins) ultimately drain into either the superior vena cava or the inferior vena cava. The superior vena cava (SVC) receives blood from the tissues and organs of the head, neck, chest, shoulders, and upper limbs. Venous Return from the Cranium Numerous veins drain the cerebral hemispheres. The superficial cerebral veins and small veins of the brain stem empty into a network of dural sinuses , including the superior and inferior sagittal sinuses, the petrosal sinuses, the occipital sinus, the left and right transverse sinuses, and the straight sinus. The largest, the superior sagittal sinus, is in the falx cerebri. Most of the inferior cerebral veins converge within the brain to form the great cerebral vein, which delivers blood from the interior of the cerebral hemispheres and the choroid plexus to the straight sinus. Other cerebral veins drain into the cavernous sinus with numerous small veins from the orbit. Blood from the cavernous sinus reaches the internal jugular vein through the petrosal sinuses . The venous sinuses converge within the dura mater in the region of the lambdoid suture. The left and right transverse sinuses begin at the confluence of the occipital, sagittal, and straight sinuses. Each transverse sinus drains into a sigmoid sinus, which penetrates the jugular foramen and leaves the skull as the internal jugular vein, descending parallel to the common carotid artery in the neck. Vertebral veins void the cervical spinal cord and the posterior surface of the skull. These vessels ©2018 Achieve Test Prep Page 271 of 367