19 terms

anatomy heart

base of heart
posterior surface
Pericardium- fibrous pericardium
tough, inelastic, dense irregular connective tissue
prevents overstretching, protection, anchorage
Pericardium-serous pericardium
thinner, more delicate membrane-double layer (parietal layer fusted to fibrous pericardium, visceral layer also called epicardium)
outer (external) layer
visceral layer of serous pericardium
smooth, slippery texture to outermost surface
95% of heart is cardiac muscle
inner layer-smooth lining for chambers of heart, valves and continuous with lining of large blood vessels
2 atria chambers
receiving chambers
auricles increase capacity
2 ventricle chambers
pumping..larger and muscular
sulci grooves
contain coronary blood vessels
coronary sulcus
anterior interventricular sulcus
posterior interventricular sulcus
sulcus surrounds the chambers
artrioventricular valves
tricuspid (between right atrium and ventricle) and bicuspid (between left artrium and ventricle)
right ventricle
pumps (deoxygentated) blood to lungs
shorter distance, lower pressure, less resistance
left ventricle
pumps (oxygenated) blood to body
longer distance, higher pressure, more resistance
works harder to maintain same rate of blood flow as right ventricle
semilunar valves
aortic and pulmonary valves
opens when pressure in ventricle exceeds pressure in arteries
as ventricles relax, some backflow permitted, blood fills valve cusps closing them tightly
systemic circuit
left side of heart...receives blood from lungs.. ejects blood into aorta..systemic arteries, arterioles..gas and nutrient exchange in systemic capillaries..sytemic venules and veins lead back to right atrium
pulmonary circuit
right side of heart...receives blood from systemic circulation...ejects blood into pulmonary trunk then pulmonary arteries...gas exchange in pulmonary capillaries...pulmonary veins takes blood to left atrium
coronary circulation
myocardium...own network of blood vessels, coronary ateries branch from ascending aorta-anastomoses provide alternate routes
allows heart muscle to receive sufficient oxygen even if artery is partially blocked
coronary capillaries, coronary veins-collect in coronary sinus and empires into right atrium
contractile fibers have stable resting membrane potential
period of maintained depolarization..time for atria to contract
recovery of resting membrane potential