SPH K 409: Exam 2 Test Questions
With Complete Answers.
Cardiovascular path through the heart - Answer right atrium --> right ventricle --> pulmonary
artery --> lungs --> left atrium --> left ventricle --> aorta --> systemic circulation
Path of electrical conduct in the heart - Answer 1. SA Node (located in right atrium)
depolarizes. Creates action potential. Intrinsic pacemaker.
2. electrical impulse spreads through both right and left atria
3. atria contract
4. impulse reaches AV node
5. impulse travels through AV bundle and Purkinje fibers to all parts of the ventricles.
6. ventricles contract
Conduction velocity speed changes throughout the heart - Answer 1. Atrial muscle --> AV
node -.5 m/sec
2. AV node --> Bundle of His -.5 to -2 m/sec
3. Bundle of His --> Left and right bundle branches -2 m/sec
4. Left and right bundle branches --> Ventricular muscle -2 to -.5 m/sec
5. Ventricular muscle --> Purkinje fibers -.5 to -4 m/sec
starts very slow and then speeds back up to make sure signal reaches all bundle branches in a
timely manner
ECG electrical tasks - Answer P wave- atria depolarize
QRS complex- ventricles depolarize
T wave- ventricles repolarize
ECG mechanical tasks - Answer P wave- atria contract
QRS complex- ventricles contract
T wave- ventricles relax
Note: don't see atria relax
Heart rate is controlled by 3 factors - Answer 1. sympathetic- increases HR
2. parasympathetic- decreases HR
3. hormones mostly increase HR (exercise or scary movie)
, What if there was no parasympathetic influence on the heart? - Answer resting heart rate
would be about 100 bpm
What happens to the heart at low workloads? (effected by parasympathetic or sympathetic?) -
Answer HR increases by DECREASING parasympathetic drive
What happens to the heart at higher workloads? (effected by parasympathetic or sympathetic?)
- Answer HR increases by INCREASING sympathetic drive
Systole - Answer contraction phase of heart. During systole, hearts chambers EXPEL blood.
(atrial and ventricular)
systolic blood pressure - Answer pressure in the arterial system during systole. (normal is
120 mmHg).
Diastole - Answer relaxation phase of the heart. During diastole, the hearts chambers FILL
with blood. (atrial and ventricular)
diastolic blood pressure - Answer pressure in the arterial system during diastole (normal is
80 mmHg)
Pressure drives flow - Answer higher --> lower pressure
Brachial arterial pressures - Answer Systole: 120-130 mmHg
Diastole: 70-80 mmHG
Mean right atrial pressure - Answer 5 mmHg
Right ventricular pressures - Answer systole: 25 mmHg
diastole: 5 mmHg
Pulmonary arterial pressures - Answer systole: 22 mmHg
diastole: 10 mmHg
mean left arterial pressure - Answer 7 mmHg
With Complete Answers.
Cardiovascular path through the heart - Answer right atrium --> right ventricle --> pulmonary
artery --> lungs --> left atrium --> left ventricle --> aorta --> systemic circulation
Path of electrical conduct in the heart - Answer 1. SA Node (located in right atrium)
depolarizes. Creates action potential. Intrinsic pacemaker.
2. electrical impulse spreads through both right and left atria
3. atria contract
4. impulse reaches AV node
5. impulse travels through AV bundle and Purkinje fibers to all parts of the ventricles.
6. ventricles contract
Conduction velocity speed changes throughout the heart - Answer 1. Atrial muscle --> AV
node -.5 m/sec
2. AV node --> Bundle of His -.5 to -2 m/sec
3. Bundle of His --> Left and right bundle branches -2 m/sec
4. Left and right bundle branches --> Ventricular muscle -2 to -.5 m/sec
5. Ventricular muscle --> Purkinje fibers -.5 to -4 m/sec
starts very slow and then speeds back up to make sure signal reaches all bundle branches in a
timely manner
ECG electrical tasks - Answer P wave- atria depolarize
QRS complex- ventricles depolarize
T wave- ventricles repolarize
ECG mechanical tasks - Answer P wave- atria contract
QRS complex- ventricles contract
T wave- ventricles relax
Note: don't see atria relax
Heart rate is controlled by 3 factors - Answer 1. sympathetic- increases HR
2. parasympathetic- decreases HR
3. hormones mostly increase HR (exercise or scary movie)
, What if there was no parasympathetic influence on the heart? - Answer resting heart rate
would be about 100 bpm
What happens to the heart at low workloads? (effected by parasympathetic or sympathetic?) -
Answer HR increases by DECREASING parasympathetic drive
What happens to the heart at higher workloads? (effected by parasympathetic or sympathetic?)
- Answer HR increases by INCREASING sympathetic drive
Systole - Answer contraction phase of heart. During systole, hearts chambers EXPEL blood.
(atrial and ventricular)
systolic blood pressure - Answer pressure in the arterial system during systole. (normal is
120 mmHg).
Diastole - Answer relaxation phase of the heart. During diastole, the hearts chambers FILL
with blood. (atrial and ventricular)
diastolic blood pressure - Answer pressure in the arterial system during diastole (normal is
80 mmHg)
Pressure drives flow - Answer higher --> lower pressure
Brachial arterial pressures - Answer Systole: 120-130 mmHg
Diastole: 70-80 mmHG
Mean right atrial pressure - Answer 5 mmHg
Right ventricular pressures - Answer systole: 25 mmHg
diastole: 5 mmHg
Pulmonary arterial pressures - Answer systole: 22 mmHg
diastole: 10 mmHg
mean left arterial pressure - Answer 7 mmHg
