Heart Quiz Flashcards
heart wall layers (inner to outer)
endocardium, myocardium, epicardium, pericardial cavity
endocardium
- inner lining of the heart wall
- continuous with the vasculature
what is the endocardium known as in blood vessels
endothelium
myocardium
- biggest layer
- ## thick muscular layer
myo- meaning
muscle
what type of tissue of endocardium
loose areolar CT
what is myocardium made of
cardiomyocytes (cells that make up cardiac muscle)
cardiac muscle
- highly branched short striated muscle with 1 nucleus
- connected with intercalated discs (special channel protein) that allow for free exchange between cells
epicardium (of heart walls)
- loose CT and epithelia
- visceral pericardium
pericardial cavity
- filled with serous (watery) fluid
- reduces friction and provides protection
4 valves
atrioventricular valves and semilunar valves
atrioventricular valves
- tricuspid valve (3 cusps; between right atrium and ventricle)
- bicuspid aka mitral valve (2 cusps; between left atrium and ventricle)
semilunar valves
- pulmonary semilunar valve (between the right ventricle and pulmonary artery)
- aortic semilunar valve (between the left ventricle and aorta)
chordae tendinae
anchors the cusps of the AV valves to the walls of the ventricles
av valve process
- when the heart is relaxed blood passively fills the atriums, the AV valve cusps hang limp
- when the ventricles contract they press on the blood in the chambers and pressure forces the AV valve to close upwards
- the chordae tendinae anchor the valves to make sure they do not blow into the atria
semilunar valve process
- when ventricles contract the cusps are opened and flattened against the walls of the artery
- when the ventricles relax the blood begins to flow back toward the ventricle and the cusps fill with blood, closing them
when are av valves open / closed
during heart relaxation / during ventricle contraction
when are semilunar valves open / closed
during ventricle contraction / during heart relaxation
pulmonary circuit course
right ventricle → lungs → left atrium
pulmonary circulation function
to carry blood to the lungs for gas exchange and return it to the heart
systemic circuit course
left ventricle → body tissue → right atrium
systemic circulation function
supplies oxygen and nutrient-rich blood to the body organs
circulatory system
vena cava (vein) → right atrium → tricuspid valve → right ventricle → pulmonary semilunar valve → pulmonary trunk (artery) → pulmonary arteries → lungs → pulmonary capillaries → pulmonary veins → left atrium → bicuspid (mitral) valve → left ventricle → aortic valve → aorta → rest of body → vena cava
do the RA + RV or LA + LV have the thicker muscle and why
LA / LV; pushes the blood throughout the entire body
which vein / artery empties at the coronary sinus
great cardiac vein
