BIOL 153 Chapter Notes -Theca Interna, Tunica Media, Arteriole
Document Summary
Muscular arteries (cid:0) arterioles (cid:0) capillaries (cid:0) venules (cid:0) veins. Large vessels, up to 2. 5 cm in diameter. These vessels have to cope with large pulsatile changes in pressure. The stretch in these arteries serves to dampen out the pulsatile changes in bp. Specifically, during ventricular diastole, the elastic recoil of these arteries serve to keep bp elevated. They have much more elastic walls than the muscular arteries. They have a thicker tunica interna (endothelium and internal elastic layer). They have a thinner tunica intermedia (smooth muscle layer). Also known as distribution arteries or medium-sized arteries. These are the arteries that carry the blood to the organs and muscles. Typically they have a diameter of about 0. 4 cm. They have a thinner tunica interna and a thicker tunica media. These vessels are much smaller than the arteries (~ 30 m or less). The tunica media consists of one or two thin layers of smooth muscle.
