Heart Flashcards
what are the types of fibres in the hearts conduction system called?
autorhythmic fibres
on an ECG what does the QRS complex represent
depolaroization of ventricles
order if firing in conduction system
SA node
AV node
Av bundle of his
bundle branches
purkinje fibres
what are the2 layers of the pericardium
fibrous
serous
what is the heart muscle called
myocardium
what is the function of the auricle
increase the capacity of the atria
what 3 large veins drain into the right atrium
coronary sinus
inferior vena cava
superior vena cave
where are pectinate muscles found
walls of atrium
trabeculae carnea are what?
muscles inside ventricles helping convey electricity
which valves connect right atrium to the right ventricle
tricuspid
once blood has left the heart what is the first branch of the aorta
coronary arteries
what is the mechanism for valves to open and close in the heart
pressure changes
the 2 semilunar valves are
aortic and pulmonary
what attaches AV valves to the wall of the heart
chrodae tendinae
when papillary muscles are relaxed the chordae tendinae are also slack - is the valve open or closed
open
pulmonary circulation is the blood flowing from which chamber to what chamber
right ventricle into pulmonary valve into pulmonary trunk into lungs
branches of the coronary arteries
LEFT - anterior interventricular, circumflex = LAC
RIGHT = posterior interventricular, marginal branch = RPM
Which veins drain into coronary sinus
MAGS
middle cardiac vein
anterior cardiac vein
great cardiac vein
small cardiac vein
what starts action potential in myocardium in the heart
SA node (natural pacemaker)
during depolarization in heart muscle fibre, the action potential stimulates
Na+ to open and Na+ to rush in
diff types of muscle in body, which moves food and urine
smooth
what’s unique to cardiac muscle tissue
desmosomes, intercalated discs, gap junctions
where does cardiac muscle tissue get energy from
aerobic respiration
during ventricular systole what are the ventricles in the atria doing
ventricles = contracting
atria = relaxing
what cranial nerve slows down heart rate
vagus
baroreceptors detect,where are they located
pressure and stretch - located in carotid and aortic arch
chemicals that help regulate heart rate
epinephrine
norepinephrine
