Heart Flashcards
Which area is NOT characterised by spontaneous diastole depolarisation?
A. Sinus node
B. AV node
C. His bundle
D. Tawara stems
E. Ventricular working muscle
E. Ventricular working muscle
Choose the only right answer!
Which phase of the ventricular action potential has the highest sodium conductance?
A. Ascending stem
B. Plato phase
C. Repolarization
D. During the resting phase following repolarisation
E. Does not change significantly during the ventricular cardiac cycle
A. Ascending stem
Choose the only CORRECT answer!
In which phase of the ventricular action potential is the largest a
calcium conductance?
A. Ascending stem
B. Platonic phase
C. Repolarization
D. During the resting phase following repolarization
E. It does not change significantly during the ventricular cardiac cycle
B. Platonic phase
Choose the only CORRECT answer!
Which ion channels are responsible for the opening of the ventricular action
for the formation of a plateau phase characteristic of potential?
A. Ca channels
B. Na canals
C. The inwardly rectifying potassium channels
D. Late potassium channels
E. None, because the Na-K pump alone can a
to form a plateau phase.
A. Ca channels
Hypercalcemia initially increases the force of heart contractions
BECAUSE
Ca ions play an important role in Na and K permeability
B
If the Ca content of the extracellular space is reduced, the action potential plateau is shifted towards more positive potentials,
BECAUSE
the Ca current below the plateau will be lower.
The letter of the correct answer is: D CORRECT!
Plato phase of the action potential of ventricular myofibres stimuli applied during the action phase of the potential,
BECAUSE
the membrane is in absolute refractory phase under the plateau.
A
The human heart muscle cannot be tetanised,
BECAUSE
contraction time does not significantly exceed the absolute refractory phase.
A
The complete removal of extracellular Ca does not affect the the magnitude of cardiac contractions,
BECAUSE
the total amount of Ca required by the human heart for contraction is released from internal stores.
E
If the His bundle is cut
A. the propagation speed of atrial contractions is twice as high
will be like before the cut
B. the frequency of ventricular contractions will be 30-40/min
C. the PQ interval does not change
D. the shape of the QRS complex changes from contraction to contraction
E. none of the statements are true
B. the frequency of ventricular contractions will be 30-40/min
Choose the only WRONG statement. If all are correct,
choose It!
In the pacemaker cells of the heart
A. the membrane potential changes continuously
B. the absolute magnitude of the membrane potential is always smaller,
like the resting potential of other cells of the heart
C. the temporal change of the membrane potential ceases if a
heart is denervated
D. spontaneous diastolic depolarization becomes steeper
under the influence of sympathetic stimulation
E. all statements are true
C. the temporal change of the membrane potential ceases if a
heart is denervated
ANSWER USING THE KEY BELOW!
A. if statements 1, 2 and 3 are correct
B. if statements 1 and 3 are correct
C. if statements 2 and 4 are correct
D. if statement 4 is correct
E. if all statements are correct
Purkinje fibers
1. they conduct the stimulus faster than the working muscle
fibers.
2. they increase the formation of heterotopic stimuli
probability.
3. they allow all areas of the chamber
contract practically simultaneously.
4. they delay the systole during the filling of the ventricle
B
The extra systole of the ventricular origin is longer than normal, followed by a longer than normal so-called compensatory pause
BECAUSE
the myocardium receives the next impulse from the sinus during the refractory period following extrasystole.
A
Under physiological conditions, the S-T section of the ECG is isoelectric
BECAUSE
the S-T phase of the ECG, the ventricular base and the ventricular apex are both at rest.
C
If the cannula of the isolated frog heart is filled with 120 mM potassium Ringer’s solution, the amplitude of contractions increases
BECAUSE
The increase the concentration of potassium in myocardial cells are depolarised.
D
Choose the only CORRECT answer!
In the human heart, where is the conduction of the stimulus fastest?
A. Sinus node
B. Atrial working muscle
C. AV node
D. Tawara stems (brunch bundles)
E. Ventricular working muscle
D. Tawara stems (brunch bundles)
ANSWER USING THE KEY BELOW:
A. if statements 1, 2 and 3 are correct
B. if statements 1 and 3 are correct
C. if statements 2 and 4 are correct
D. if statement 4 is correct
E. if all statements are correct
The minute volume
1. the amount of blood discharged from the right and left side of the heart in 1 minute
amount
2. it can increase or decrease as the heart rate increases
too
3. reflexively decreases in a warm environment
4. may increase when moving from a standing position to a lying position
person
C CORRECT!
Ventricular contraction is complete only during atrial systole
begins after its completion
BECAUSE
AV node conduction is slow.
A
The increase in the filling of the heart is the large blood circulation artery
does not affect blood pressure
BECAUSE
the arterial blood pressure is the cardiac output and the
function of peripheral resistance.
D
In the same amount of time, the right side of the heart does less work than the left
BECAUSE
Less blood flows through the small blood vessels in the same amount of time, than in the large blood vessels.
C
CHOOSE THE CORRECT ANSWER! IF NONE OF THE ANSWERS ARE CORRECT, CHOOSE
ET!
When the heart rate increases:
A. the duration of the ventricular action potential does not change
B. the ratio of systole and diastole time does not change
C. the amplitude of the contractions does not change
D. diastole time does not change
E. none of the statements are correct
The letter of the correct answer is: E CORRECT!
Choose the only WRONG statement.
When stimulating the sympathetic nerve fibers running to the heart
A. the frequency of stimulation increases
B. impulse conduction is accelerated
C. contractility increases
D. the resistance of the coronary arteries increases
E. end-diastolic volume decreases
The letter of the correct answer is: D CORRECT!
Match the combinations below with the appropriate statement.
Swells under the influence of sympathetic stimulation
A. the contraction force of the heart muscle
B. the heart rate
C. both
D. none of them
The letter of the correct answer is: C CORRECT!
Match the combinations below with the appropriate statement.
It is proportional to the end-diastolic volume of the ventricle
A. the pulse volume
B. the heart rate
C. both
D. none of them
A
Match the combinations below with the appropriate statement.
It usually increases when venous return increases
A. the pulse volume
B. the heart rate
C. both
D. none of them
The letter of the correct answer is: C CORRECT!
Match the combinations below with the appropriate statement.
As a result of training, it grows at rest
A. the pulse volume
B. the heart rate
C. both
D. none of them
A
ANSWER USING THE KEY BELOW:
A. if statements 1, 2 and 3 are correct
B. if statements 1 and 3 are correct
C. if statements 2 and 4 are correct
D. if statement 4 is correct
E. if all statements are correct
When the sympathetic tone increases
1. between the initial tension of the heart muscle and the contraction force
relationship changes, lower force for a given fiber length
belongs to
2. the amount of blood flowing through the coronary arteries decreases
3. the speed of atrio-ventricular conduction slows down
4. spontaneous diastolic depolarization of the pacemaker cells
speed increases
The letter of the correct answer is: D CORRECT!
ANSWER USING THE KEY BELOW:
A. if statements 1, 2 and 3 are correct
B. if statements 1 and 3 are correct
C. if statements 2 and 4 are correct
D. if statement 4 is correct
E. if all statements are correct
In a healthy adult
1. the vagus exerts a pronounced inhibitory effect on
for heart rate
2. suspension of the vagus effect for approx. Increases by 50%
heart rate
3. the vagus effect is also regulated by reflex processes
4. Vagus stimulation does not affect the contractility of the atrial muscle
influence
A
The heart muscle can be tetanized by stimulating the sympathetic fibers
BECAUSE
another contraction can be induced in the relative refractory section.
The letter of the correct answer is: D CORRECT!
Adrenaline’s cardiac effects can be prevented by administering atropine
BECAUSE
adrenaline primarily binds to beta receptors in the heart
it exerts its effect when bound.
The letter of the correct answer is: D CORRECT!
In individuals used to physical work, the minute volume hardly changes
in the case of performing physical work
BECAUSE
our heart to physical work instead of increasing cardiac output
it usually adapts by increasing the pulse volume.
The letter of the correct answer is: E CORRECT!
Choose the only CORRECT statement! If all are incorrect,
choose It!
The PQ time on the ECG picture:
A. corresponds to the duration of ventricular depolarization
B. corresponds to the duration of ventricular repolarization
C. corresponds to the atrio-ventricular conduction time
D. two-thirds of the current cardiac cycle
E. none of the statements are correct
The letter of the correct answer is: C CORRECT!
Choose the only CORRECT statement! If all are incorrect,
choose It!
At the beginning of which phase of the cardiac cycle does the II. heartbeat?
A. isotonic contraction
B. isometric contraction
C. isometric relaxation
D. isotonic relaxation
E. none of the above
The letter of the correct answer is: C CORRECT!
Choose the only WRONG statement.
A. during isometric contraction, the AV and semilunar
keys are locked
B. at the end of the isometric contraction, the AV keys open
C. during isotonic contraction, the ventricles empty
D. during diastole, the higher pressure prevailing in the aorta
closes the semilunar keys
E. incomplete closure of the tricuspid valves is severe
causes circulatory disorders
The letter of the correct answer is: B CORRECT!
Choose the only CORRECT statement! If all are incorrect,
choose It!
At the beginning of which phase of the cardiac cycle does the first heart sound occur?
A. isotonic contraction
B. isometric contraction
C. isometric relaxation
D. isotonic relaxation
E. none of the above
The letter of the correct answer is: B CORRECT!
