Exam II Flashcards
Rapid calcium influx occurs during which phase of the rhythmic action?
Phase 0
Phase 1
Phase 2
Phase 3
Phase 0
Increase in sodium influx occurs during which phase of myocardial action potential?
Phase 0
Phase 1
Phase 2
Phase 3
Phase 0
Increase in calcium for subsequent contraction occurs during which phase of the myocardial action potential?
Phase 0
Phase 1
Phase 2
Phase 3
Phase 2
Sympathetic stimulation will cause which of the following?
Decreased stroke volume
Decreased cardiac output
Cutaneous vasoconstriction
Coronary vasodilation
Cutaneous vasoconstriction
Coronary vasodilation
Which will not cause sympathetic stimulation?
Systemic vasodilation
Venular vasdilation
Arteriolar vasoconstriction
Systemic vasodilation
The rate of impulse generation is fastest in which of the following?
Purkinje system
Bundle of his
AV node
SA node
SA node
Speed of conduction of the myocardial action potential is the fastest in which of the following?
Purkinje system
Bundle of his
AV node
SA node
Purkinje system
A week ventricular myocardium can result in what?
Decreased stroke volume
Decreased cardiac output
Bradycardia
Tacticardia
Decreased stroke volume
Decreased cardiac output
Arteriolar constriction is mediated by vascular receptors?
Muscarinic ACh
Alpha-adrenergic
Beta-adrenergic
Nicotinic
Alpha-adrenergic
Which of the following is not a vasoactive substance?
Renin
Epinephrine
Norepinephrine
AG I
Renin
Which of the following will not cause arteriolar constriction?
Renin
Epinephrine
AG I
AG II
Renin
Which of the following statements is correct regarding venous return?
Exercise will cause venous return to increase
Decreased venous return will decrease stroke volume
Sympathetic stimulation will dilate veins increasing venous return
Valves prevent flow from reaching heart
Exercise will cause venous return to increase
Decreased venous return will decrease stroke volume
Sensory signals from baroreceptors in carotid sinus are carried to nucleus of the solitary tract of which of the following fibers?
Descending CN IX
Descending CN X
Ascending CN IX
Ascending CN X
Ascending CN IX
Sensory signals from the baroreceptors in the aortic arch are transmitted by parasympathetic fibers of
CN X
CN IX
CN IV
CN IIV
CN X
The substance that increases blood volume by retaining sodium from the ECF is which of the following?
Renin
Aldosterone
ADH
Angiotensin converting enzyme
Aldosterone
Myocardial contractility depends upon adequate concentration of which of the following cations?
Calcium
Potassium
Sodium
Magnesium
Calcium
Rapid repolarization phase of the plateau action potential occurs due to which of the following events?
Sodium ion influx
Sodium ion efflux
Potassium ion influx
Potassium ion efflux
Potassium ion efflux
Slow depolarization in cells of the SA node are due to influx of which ions?
Sodium
Potassium
Chloride
Calcium
Sodium
A person with hyper-aldosteronism will present with which of the following?
Increased blood volume
Hyperkalemia
Hypokalemia
Hypotension
Increased blood volume
Hypokalemia
Which of the following conditions will cause systematic arterial blood pressure to rise?
Hypo-aldosteronism
Excessive plasma ADH
Vagal stimulation
All of the above
Excessive plasma ADH
All of the following except ____ will cause systemic blood pressure to rise?
Increased vagal tone
Increased cardiac output
Increased aldosterone
None of the above
Increased vagal tone
Which hormone causes only water retention?
ADH
Aldosterone
Angio converting enzyme
Atrial natriuretic peptide
ADH
Which hormone causes NA+ excretion?
ADH
Aldosterone
Angiotensin converting enzyme
Atrial natriuretic peptide
Atrial natriuretic peptide
Which is not correct regarding the myocardium?
Muscle contractions are always preceded by muscle action potentials
Both atria contract simultaneously
Ventricular contractions are delayed after atria contract
Hypocalcemia will cause stroke volume to increase
Hypocalcemia will cause stroke volume to increase
The normal electrical axis of the heart is what?
0
60
120
180
60
Fastest rate of slow depolarization; normal pacemaker
SA node
Depolarization due to calcium influx
AV node
Cells are deficient in gap junctions; relatively thin fibers and fewer gap junctions
AV bundle
Primer pump; repolarization is not represented in the EKG
Atrial myocardium
QRS complex of the EKG represents depolarization; contraction determines cardiac output
Ventricular myocardium
First heart sound occurs
Period of isometric contraction
Semilunar valves open
Period of ejection
Dicrotic notch on BP curve
Period of isovolmetric relaxation
Occurs after the 2nd heart sound
Period of passive filling
Occurs during PR segment
Period of active filling
Sympathetic stimulation will cause vasoconstriction in which of the following circulatory beds?
Coronary
Cutaneous
Cerebral
Pulmonary
Cutaneous
Arteriolar diameter is predominately dependent upon sympathetic tone in which of the following vascular beds?
Coronary
Cutaneous
Cerebral
Pulmonary
Cutaneous
Stimulation of which of the following will decrease heart rate?
Adrenergic receptors in the SA node
Adrenergic receptors in the myocardium
mACh receptors in SA node
mACh receptors in SA
Stimulation of which of the following will not increase systemic blood pressure?
Adrenergic receptors in SA node
Adrenergic receptors in myocardium
mACh receptors in SA node
None of the above
mACh receptors in SA node
The plateau phase of myocardial contractions is which of the following?
ECF
Mitochondria
SR
ER
ECF
Myocardial tissues function as syncitia because of which structural characteristics?
Branched nature of myocardial fiber
Gap junctions
All of the above
None of the above
All of the above
Systolic pressure in the pulmonary artery is the same as the systolic pressure in the systematic arteries.
True/False
False
Mitral valve stenosis will decrease cardiac output.
True/False
True
Mitral valve prolapse may lead to cardio-acceleration.
True/False
True
Sympathetic stimulation will decrease cardiac output.
True/False
False
A person will uncontrolled hypertension may complain of frequent urination.
True/False
True
Vagal vagal stimulation will cause sinus bradycardia.
True/False
True
Oncotic pressure draws water from the ISF to the plasma.
True/False
True
Most of the blood is contained in the veins.
True/False
True
Blood pressure, EKG, volume in heart chambers, and sounds are monitored during cardiac cycle.
True/False
True
S1 (lubb) is a result of AV valve closure.
True/False
True
Period of isovolumetric contraction -> period of ejection -> period of isovolumetric relaxation -> passive ventricular filling -> active ventricular filling
Correct order of events.
True/False
True
Baroreceptors are located in the aortic arch and in the carotid sinus.
True/False
True
Sensory signals from baro receptors are transmitted to cardiac center located in the medulla.
True/False
True