Chapter 18 - Cardiovascular System: The Heart

D. heart wall - 3 layers. 1. epicardium – see above. 2. myocardium - bulk of heart - layer that actually contracts. 3. endocardium - endothelial membrane (squamous epithelium) lines interior of heart and covers fibrous skeleton of valves. E. Chambers. 1. components. a. 2 atria - right and left-superior-receive blood-small; thin walled ................
................