Mean arterial pressure is systolic pressure plus one third pulse pressure. Arterioles in skeletal muscle receive cholinergic sympathetic fibers which release ACh. The umbilical arteries in the fetus arise from the abdominal aorta. Extrinsic regulation of blood flow refers to control by the ANS and the endocrine system. Vasopressin has a vasodilator effect at high concentrations.
Active hyperemia occurs as a result of increased metabolism.
The vasomotor control center is located in the postcentral gyrus of the parietal lobe. The walls of lymphatic capillaries are less permeable than are the walls of blood capillaries. C. axillary artery D. superior mesenteric artery E. aorta. Empties into the brachial artery. Supplies the small intestine and the ascending colon.