PHSI 208 Lecture Notes - Lecture 30: Pulmonary Circulation, Blood Vessel, Elastic Fiber
Document Summary
Cardiovascular system consists of two pumps in series: one pump controls the pulmonary circuit, the other controls the systemic circuit. Blood flows down a pressure gradient, created by the contraction of ventricles. Capillaries is the site of exchange b/w blood and cells: exchange also occurs in post-capillary venules (transport occurs here too) Aorta arteries arterioles capillaries venules veins vena cava. All contain inner layer of thin endothelial cells and can be wrapped in a combination of elastic tissue, smooth muscle or fibrous tissue: capillaries only consists of an endothelium. Endothelial cells were thought to only be a passive barrier. *these layers vary depending on what type of blood vessel it is, and not all layers may be present. The amount of smooth muscle in each vessel type varies. Vascular smooth muscle can be influenced by a variety of substances including nt, hormones, paracrines. These substances bind receptors ultimately resulting in an increase in cytosolic ca2+ causing contraction.
