P3 Chapter 20 THE HEART Flashcards
(108 cards)
Which of the following represents the correct sequence of flow of an electrical impulse through the heart?
a. AV node, AV bundle, Purkinje fibers, SA node
b. SA node, Purkinje fibers, AV node, AV bundle
c. SA node, AV node, AV bundle, Purkinje fibers
d. AV node, SA node, Purkinje fibers, AV bundle
c. SA node, AV node, AV bundle, Purkinje fibers
The cardiac cycle is regulated by the
a. cerebrum
b. thalamus
c. spinal cord
d. medulla oblongata
d. medulla oblongata
The T wave on an EKG is due to
a. atrial depolarization
b. ventricular depolarization
c. atrial repolarization
d. ventricular repolarization
d. ventricular repolarization
Internally, the right and left halves of the heart are separated by the
a. pulmonary semilunar valve
b. atrioventricular valve
c. papillary muscles
d. interatrial and interventricular septa
d. interatrial and interventricular septa
Tension in the chordae tendineae and papillary muscles during ventricular systole prevent
a. contraction of the atria
b. blood flow into the great arteries
c. eversion of the AV valves
d. closing of the valves
c. eversion of the AV valves
The sinoatrial node
a. clsontains cells which spontaneously and rhythmically generate action potentia
b. is connected to the AV node by way of Purkinje fibers
c. transmits impulses directly to the ventricular myocardium
d. is the only normal pathway for impulse conduction from the pacemaker to the ventricles
a. clsontains cells which spontaneously and rhythmically generate action potentia
The closing of the semilunar valves
a. directs blood flow into the atria
b. produces the second heart sound
c. corresponds with atrial systole
d. produces the EKG P wave
b. produces the second heart sound
Veins in the myocardium drain into the
a. posterior ventricular artery
b. coronary sinus
c. marginal artery
d. anterior interventricular artery
b. coronary sinus
When the ventricles relax
a. the semilunar valves close
b. the EKG shows a QRS spike
c. blood is forced into the ventricles
d. coronary circulation slows
a. the semilunar valves close
The right atrium receives blood directly from 3 vessels. They are the
a. superior vena cava, inferior vena cava, and left internal jugular vein
b. superior vena cava, coronary sinus, and left internal jugular vein
c. superior vena cava, inferior vena cava, and coronary sinus
d. microglia
c. superior vena cava, inferior vena cava, and coronary sinus
The left ventricle refills with blood in preparation for initiation of the next cardiac cycle during ventricular
a. systole
b. contraction
c. repolarization
d. diastole
d. diastole
Asynchronous, haphazard, ventricular contractions are characteristic of
a. interventricular septal defect
b. coarctation of the aorta
c. ventricular fibrillation
d. Tetralogy of Fallot
c. ventricular fibrillation
Release of norepinephrine from nerve fibers causes
a. decreased heart rate and force of contraction
b. increased heart rate but decreased force of contraction
c. increased heart rate and force of contraction
d. decreased heart rate but increased force of contraction
c. increased heart rate and force of contraction
The first heart sound is associated with
a. both semilunar valves closing during ventricular diastole
b. pulmonary semilunar and tricuspid valves closing during ventricular diastole
c. both atrioventricular valves closing during ventricular systole
d. aortic semilunar and bicuspid valves closing during ventricular systole
c. both atrioventricular valves closing during ventricular systole
Which of the following represents the correct pathway of blood moving from the superior vena cava to the lungs?
a. pulmonary semilunar valve, right atrium, tricuspid valve, right ventricle
b. right atrium, pulmonary semilunar valve, right ventricle, tricuspid valve
c. right atrium, tricuspid valve, right ventricle, pulmonary semilunar valve
d. occurs only on myelinated fibers
c. right atrium, tricuspid valve, right ventricle, pulmonary semilunar valve
Nerve impulses that reach the heart by means of the vagus nerve are
a. parasympathetic and cause increased heart rate
b. parasympathetic and cause decreased heart rate
c. sympathetic and cause increased heart rate
d. sympathetic and cause decreased heart rate
b. parasympathetic and cause decreased heart rate
During repolarization of a cardiac muscle fiber
a. both Na+ and K+ move out of the cell
b. both Na+ and K+ move into the cell
c. K+ moves out of the cell
d. K+ moves into the cell
c. K+ moves out of the cell
The atrioventricular node
a. connects the bundle of His with the Purkinje fibers
b. is located in the interatrial septum
c. connects to the atrial syncytium by Purkinje fibers
d. is near the opening of the IVC, just below the epicardium of the left atrium
b. is located in the interatrial septum
Most of the heart lies
a. to the left of midline of the thoracic cavity
b. to the right of midline of the thoracic cavity
c. in the center of the thoracic cavity
d. with apex pointing toward the sternoclavicular joint
a. to the left of midline of the thoracic cavity
Blood flows from the right atrium to the right ventricle through the _____ valve
a. tricuspid
b. aortic semilunar
c. pulmonary semilunar
d. bicuspid
a. tricuspid
What is the cardiac output of a patient with a stroke volume of 70 mL/ventricular contraction whose pulse is 90 beats/minute?
a. 70 mL/minute
b. 90 beats/minute
c. 160 mL/minute
d. 6300 mL/minute
d. 6300 mL/minute
The cardiac impulse spreads into the mass of the ventricular muscle tissue from the
a. junctional fibers
b. conduction myofibers
c. the atrioventricular bundle
d. bundle branches
b. conduction myofibers
Within the heart, there is a delay in impulse transmission at the ____ in order to allow time for ________
a. SA node, atrial contraction
b. atrial syncytium, AV valve opening
c. AV node, ventricular filling
d. Purkinje fibers, SL valve closure
c. AV node, ventricular filling
Immediately prior to ventricular systole, pressure in the aorta is about
a. 2 mm Hg
b. 20 mm Hg
c. 80 mm Hg
d. 120 mm Hg
c. 80 mm Hg























