Endocardium -(correct answer)The innermost layer of the heart, it forms the lining and folds
back onto itself to form the four valves. It is in this layer that the conduction system is found
Myocardium -(correct answer)Muscular layer of the heart Epicardium -(correct answer)The
outermost layer of the heart. It is actually the inner layer of the pericardium Right atrium
-(correct answer)Receives deoxygenated blood returning to the heart from the body via the
superior vena cav which carries blood from the upper body and the inferior vena cava which
carries blood from the lower body. Right ventricle -(correct answer)Receives deoxygenated
blood from the right atrium which pumps to the lungs for oxygenation through the pulmonary
artery (trunk) to the right and left pulmonary arteries Left atrium -(correct answer)Receives
oxygenated blood returning from the lungs via the right and left pulmonary veins. Left ventricle
-(correct answer)Receives the oxygenated blood from the left atrium and pumps it to the body
through the aorta, the largest artery of the body. The two semilunar valves -(correct
answer)Pulmonic valves and aortic valves Heart Sounds S1 -(correct answer)First heart sound
is due to the closure of the mitral and tricuspid valves Heart Sounds S2 -(correct
answer)Second heart soudn is due to closure of the aortic and pulmonic valves Coronary
arteries -(correct answer)The arteries supplying the heart with blood Sympathetic Nervous
System -(correct answer)Affects both the ventricles and atrium by increasing heart rate,
conduction and irritability Parasympathetic Nervous System -(correct answer)Affects the atria
only by decreasing heart rate, conduction and irritability Automaticity -(correct answer)This is
the ability of the cardiac cells to stimulate their own electrical impulse without being stimulated
from another source Excitability -(correct answer)Irritability, shared by all cardiac cells and it
the ability to respond to external stimulus; electrical, chemical and mechanical Conductivity
-(correct answer)This is the ability of all cardiac cellls to receive and electrical stimulus adn
transmit the stimulus ot the other cardiac cells Contractility -(correct answer)This is the ability
of the cardiac cells to shorten and cause cardiac muscle contraction in response to an
electrical stimulus SA node -(correct answer)Primary pacemaker of the heart, instrinisc rate of
60 -100 beats per minute AV node -(correct answer)Located at the posterior septal wall of the
right atrium, just above the tricuspid valve. There is a 1/10th of a second delay of electrical
activity at this level to allow the blood to flow from the atria to the ventricles. Intrinsic rate of
40-60 beats per minute Bundle of His -(correct answer)Found at the superior portion of the
interventricular septum, it is the pathway that leads to the SA node. Intrinsic rate 40-60 beats
per minute. Bundle Branches -(correct answer)Located at the interventricular septum. The
bundle of His divides into the right and left bundle branches. The function is to conduct the
electrical impulse to the purkinje fibers. Purkinje Fibers -(correct answer)Found within the
ventricular endocardium. Instrinsic rate is 20-40 beats per minute. Unipolar Precordial Leads
-(correct answer)V1,V2,V3,V4,V5 and V6 25mm/sec -(correct answer)The normal running
speed of the EKG 1 MV will produce a deflection of -(correct answer)10mm Waveform
-(correct answer)Refers to the movement away from the isoelectric line either upward (positive)