PHED-1507EL Chapter Notes - Chapter 19: Tunica Intima, Tunica Externa, Tunica Media
Document Summary
Three major types of blood vessels; arteries, capillaries and veins. As the heart contracts it forces blood into the large arteries leaving the ventricles. This blood then moves on to successively smaller arteries, eventually reaching their smallest branches; the arterioles, which then feed into the capillary beds of body organs and tissues. Blood drains from the capillaries into venules (the smallest veins) and then onto larger and larger veins that merge together to form large veins that eventually empty into the heart. Altogether the blood vessels in an adult human stretch for about 100,000km through the internal body landscape. Carry blood away from the heart, so they are said to branch , Diverge , or fork as they form smaller and smaller divisions. Carry blood toward the heart and are said to join , merge , and converge into the successively larger vessels approaching the heart. In systemic circulation, arteries always carry oxygenated blood and veins always carry oxygen-poor blood.
