Action of the Heart
1. Collects blood from the body (low 02) and pumps it to the lungs to get O2
2. Collects blood from the lungs (high 02) and pumps it to body cells that need it
left and right atria
thin walled collecting chambers (not muscular because they are not pumping)
left and right auricle
outside the left and right atria meaning "little ear
right ventricle
-pumps blood to the lungs
-has thinner wall
left ventricle
pumps blood to the body
-has thicker wall
septum
wall down the middle of atria and ventricles
tricuspid
type of AV valve on the right side, has 3 folds
bicuspid
type of AV valve on the left side, has 2 folds
semilunar valves
prevent back flow into ventricles
aortic semilunar valve
bottom of aorta on left side
pulmonary semilunar valve
bottom of pulmonary trunk on right side
aorta and aortic arch
take blood high in O2 from left ventricle to body cells
coronary arteries
supply heart muscle with oxygen and nutrients
coronary sinus
brings blood low in 02 from heart muscle back to right atrium so it can go to the lungs
superior vena cava
from above; dumps into right atrium
inferior vena cava
from below; dumps into right atrium
pulmonary trunk
leads from right ventricle
pulmonary arteries
carry blood away from the heart to the lungs
(arteries = away)
pulmonary veins
...
papillary muscles
-on floor of ventricles
-contract to hold on to the valves and tricuspid
chordae tendinae
hold the valves closed while ventricles contract
endocardium
inside"
-lines chambers
-made of epithelial cells and is what valves are made of
myocardium
muscle"
-muscular wall of heart
pericardium
around"
-outer layer (visceral pericardium, parietal pericardium)