a&p lab exam one Flashcards
define cardiac output
total amount of blood pumped per minute
what is the equation for CO
SVxHR
define stroke volume
EDV-ESV
how does increased venous return affect HR, SV, and CO
incr SV, which incr CO
how does exercise affect HR, SV, and CO
increases all
the part of the intrinsic conduction system that initiates and sets the heart rate is the …
SA node
List the parts of the intrinsic conductive system in order of how they reach the electrical signal
SA node –> AV node –> AV bundle –> AV bundle branch –> Purkinjie fibers
a tracing of the electrical activity of the heart is called an …
ECG
what does a P wave reflect
atrial depolarization
what does a QRS complex reflect
ventricular depolarization
what does a T wave reflect
ventricular repolarization
in a normal ECG wave tracing, atrial repolarization is hidden by the
ventricular depolarization
The P wave represents ___ depolarization, which leads to atrial ___.
atrial
systole
how do the waves of depolarization, generated by autorhythmic cells, spread to the muscle cells?
gap junctions
name three channels essential for generating an action potential and indicate which way the ions move
Ca2+ channels into
Na+ channels into
K+ channels out of
if the sodium channel or the calcium channels are open, the inside of the cell would be relatively more …
positive/depolarized
state the voltage-gated channels responsible for the following stagees of the action potential in cardiac contractile cells:
Depolarization
Plateau
Repolarization
Na+ gates
Ca2+ gates
K+ gates
What channels in the autorhythmic cells allow ions to leak in, producing a pacemaker potential?
Na+ channels
Where do you place stethoscope to hear Pulmonary SL valve? (on self)
just below the clavicle and to the left of the sternum
Where do you place stethoscope to hear Aortic SL valve? (on self)
just below the clavicle and to the right of the sternum
Where do you place stethoscope to hear mitral valve? (on self)
just below xiphoid process and to the left
Where do you place stethoscope to hear tricuspid valve?
just over xiphoid process
what causes heart sound 1
closure of the AV valves
what causes heart sound 2
closure of the SL valves