IMG_0002_NEW_0002 - All other organs of the circulatory...

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Widow maker Since cardiac muscle is supply. At rest, normal o utput.3!p"pro.1jnple ly coronary, vessetq D. Blood Vessels Arteries- blood.3S. highly dependent on aerobic metabolism, it has a rich blood ow to the myocardium is about 5 Yo of the total cardiac w{t They range in size from the aorta which is about 25 mm in diameteTin man to those about 0.5 mm. Going from large arteries ) medium-sized arteries ) small arteries ) arterioles, there is less elastic tissue in the wall of the artery and more smooth muscle. Arterioles - arteries under 0.5 mm in diameter By constricting or relaxing the thick layer of smooth muscle in the walls of arterioles, blood flow can be increased or decreased to various capillaries. Arleries and arterioles constitute the high pressure part of the circulatory system. Capillaries:- very tiny (10 microns diameter), thin-walled vessels.
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Unformatted text preview: All other organs of the circulatory system exist only to serve the capillary beds. Capillaries in the human body:- surface area: 6000 sq. meters (12 soccer fields)- 60,000 miles long- mass - twice the size of the liver Venules - small vessels that conduct venous blood from capillaries to veins Veins - vessels that convev blood (@D the heart. In general, veins are of greater diameter, but thinner-walled than the arteries with which they travel. There are both superficial and deep veins Veins also have smooth muscle in their walls that allow them to change their diameter The venules and the veins constitute the low pressure part of the circulatory system. Valves -lfound in those veins which carry blood against ttre&lcepferaViU especially intheveinsofthelegs # Mechanisms involved in return of blood to the heart:rl...
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This note was uploaded on 12/29/2011 for the course KIN 142 taught by Professor Asmundson during the Fall '09 term at Simon Fraser.

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