ANATOMY OF ARTERY, VEIN AND CAPILLARY

md-6 ANATOMY OF ARTERY, VEIN AND CAPILLARY

Artery This 3d model showing the largest arteries of the body contain a good proportion of elastic tissue within the internal elastic lamina and tunica media layers. The thick walls and elastic nature of arteries mean they can withstand the high pressure that occurs when the hearts contracts and also keep blood flowing between heart beats. There is less elastic tissue in smaller,muscular arteries,and even less in the smallest arteries ,or arterioles. Vein In this model of vein have much thinner walls than arteries and contain proportionately less muscle and more connective and elastic tissue. Capillaries converge to form tiny veins,or venules,which then join up to form larger veins. Most veins contain simple,pocket-like valves to keep blood flowing in the right direction. Capillary This 3d model of capillary are extremely thin,formed by just a single layer of flattened cells. This allows substances to transfer between the blood inside the capillary and the surrounding tissue. Some capillaries have pores,or fenestrations,to make the exchange of substances even easier. Size of Artery 33 x 6 x 6 cm approx. Weight 225 g approx. Size of Capillary 26 x 2 x 2 cm approx. Weight 70 g approx.