Anatomy of Blood Vessels
Be able to describe the tunics of blood vessel walls, and state the function of each layer. BLOOD VESSEL WALLS – 3 coats or tunics ? Tunica Intima, or interna ? lines the lumen ? a single layer thin of endothelium that is continuous with the endocardium of the heart ? forms smooth vessel lining ? help decrease resistance to blood flow ? Tunica Media ? bulky middle coat, composed of smooth muscle cells and sheets of elastin ?
smooth muscle under the control of the sympathetic nervous system, plays an active role in regulating (increase & decrease) the diameter of blood vessels. ? Tunica Externa, or adventitia ? outermost tunic, composed of areolar or fibrous connective tissue ? functions in support and protection Be able to correlate differences in artery, vein, and capillary structure with the functions of these vessels. ARTERIES ? have thicker walls than veins (tunica media thicker) ? expand and recoil as blood passes through Elastic Arteries
? Larger arteries need to with stand pressure fluctuations and have large amounts of elastic tissue in their media Muscular Arteries ? Smaller arteries have less elastic tissue and more smooth muscle in their media VEINS ? low pressure valves ? not subject to pressure fluctuations like arteries ? large lumen and valves to prevent back flow CAPILLARIES ? tiny transparent, one cell layer thick ? consist of the endothelium underlain by a basal lamina (tunica intima) ? exchange between the blood and tissue cells is easy because it’s one layer thick
Be able to recognize a cross-sectional view of an artery and vein when provided with a microscopic view and be able identify the structural layers for each slide that’s visible. SLIDE: – Artery and Vein, ID: 3 layers- tunica intima or interna, tunica media, and tunica externa or adventitia Be able to identify the following arteries and veins listed below using the human torso model. External Iliac Artery? Internal Iliac Artery Right Common Carotid Artery? Left Common Carotid Artery Descending Abdominal Aorta ? External Carotid Artery
Descending Thoracic Aorta Renal Artery Saphenous Artery External Jugular Vein? Internal Jugular Vein Subclavian Vein Brachial Vein Precava (SVC) Postcava (IVC) Renal Vein Internal Iliac Vein? External Iliac Vein Great Saphenous Vein Be able to point out and/or discuss the unique features of special circulations (hepatic portal system, circle of Willis, pulmonary circulation, fetal circulation) in the body. Be able to identify the different layers of the blood vessels and structures given by instructor on the artery-vein model.