Arteries and Veins PDF

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Summary

Arteries and Veins as a general overview. Might be helpful to read through before doing the unit....

Description

Arteries: -oxygenated blood under pressure from heart (pressure is reduced in capillaries so veins are low pressure) - often thicker walls (smooth muscle & elastin) & smaller diameter than veins - no valves apart from origins at heart (aortic & pulmonary) - large & medium sized arteries are named. Name is often similar to name of accompanying vein. - veins are often superficial to arteries to facilitate blood flow

Nerves: - penetrate wall & are mostly sympathetic (with accompanying sensory fibers) - ROLE - vasomotor - usually involved in contraction of smooth muscle in the wall of the vessel (in skin) or in some instance of dilation eg: in skeletal muscle - HITCH HIKERS - not involved in arterial function - remain on outside of wall - can be SYMPATHETIC or parasympathetic or sensory or a combination....