The Heart Flashcards
(22 cards)
What kind of chambers are the atria?
receiving chambers
small, thin-walled chambers
not much movement - little propulsion of blood
what are auricles and where are they located?
appendages that increase atrial volume
little tongues off the atria
describe the right atrium
receives deoxygenated blood from body
anterior portion is smooth-walled
posterior portion contains ridges formed by pectinate muscle
what separates the posterior and anterior atria?
crista terminalis
what three veins empty into the right atrium?
1 - SVC: returns blood from above the diaphragm
2 - IVC: returns blood from below the diaphragm
3: coronary sinus: returns blood from coronary veins
describe the left atrium
received oxygenated blood from lungs
pectinate muscles found only in auricles
4 pulmonary veins return blood from lungs
what kind of chambers are the ventricles?
discharging chambers
make up most volume of the heart
thicker walls than atria
actual pumps of the heart
where is the right ventricle located? left?
right: most of anterior surface - pumps blood into pulmonary trunk
left: posteroinferior surface - pumps blood into aorta
what is trabeculae carneae?
irregular ridges of muscle on ventricular walls
what are papillary muscles?
project into ventricular cavity
anchor chordae tendineae attached to heart valves
what do the atrioventricular (AV) valves do?
prevent backflow into atria when ventricles contract
what is the tricuspid valve?
right AV valve
made up of three cusps and lies between right atria and ventricle
what is the mitral valve?
left AV valve
made up of two cusps and lies between left atria and ventricle
what does the chordae tendineae do?
anchor cusps of AV valves to papillary muscles that function to:
- hold valve flaps in closed position
- prevent flaps from everting back into atria
what do the semilunar valves do?
prevent backflow from major arteries back into ventricles
- open and close in response to pressure changes
- each valve has 3 cusps that resemble a half moon
where is the pulmonary semilunar valve located?
between right ventricle and pulmonary trunk
where is the aortic semilunar valve located?
between left ventricle and aorta
what is the pathway through the right side of the heart?
SVC, IVC, coronary sinus right atrium tricuspid valve right ventricle pulmonary semilunar valve pulmonary trunk right and left pulmonary arteries (deoxygenated blood) lungs
what is the pathway of the left side of the heart?
four pulmonary veins left atrium bicuspid valve left ventricle aortic semilunar valve aorta systemic circulation (rest of body)
what kind of circulation is the pulmonary circuit?
short, low pressure circulation
what kind of circulation is the systemic circuit?
circuit is long, high-friction circulation
which ventricle wall is thicker and why?
left ventricle wall
- pumps with greater pressure
