Question 1

In which of the following situations would the end-systolic volume (ESV)be the greatest?

Accepted Answer

A)  when sympathetic stimulation of the heart is increased 
B)  when parasympathetic stimulation of the heart is increased 
C)  when the force of myocardial contraction is increased 
D)  when the intracellular stores of calcium are increased 
E)  when stroke volume is increased

Question 2

Acetylcholine slows the heart rate by

Accepted Answer

A)  just increasing ion influx, thus increasing the rate of depolarization. 
B)  just increasing the permeability to Ca²⁺. 
C)  just increasing the permeability to K⁺. 
D)  just decreasing the permeability to Ca²⁺. 
E)  increasing the permeability to K⁺ and decreasing the permeability to Ca²⁺.

Question 3

Atropine inhibits parasympathetic activity.Discuss the effects of atropine on the heart and describe common expected side effects.

Accepted Answer

The answer of Atropine inhibits parasympathetic activity.Discuss the effects of...

Question 4

Electrical shock to the heart is usually used to treat

Accepted Answer

A)  ventricular fibrillation. 
B)  atrial fibrillation. 
C)  heart block. 
D)  heart murmur. 
E)  myocardial infarction.

Question 5

During the cardiac cycle,

Accepted Answer

A)  the P wave of the ECG occurs between the first and second heart sounds. 
B)  the QRS complex of the ECG precedes the increase in ventricular pressure. 
C)  the third heart sound occurs during atrial systole. 
D)  the second heart sound coincides with the QRS complex of the ECG. 
E)  the greatest increase in ventricular pressure occurs during the ejection phase.

Question 6

Match the change with the cardiovascular event described.
-You suck milk through a 6-inch straw and through a 10-inch straw; the diameters are identical.Resistance is ________ in the 10-inch straw compared to the 6-inch straw.

Accepted Answer

A) increased 
B) decreased 
C) unchanged 
D) stopped

Question 7

Compare the flow rates (Q)of tubes one and two, assuming the following parameters:
 $$\text { Tube one: } \Delta \mathrm { P } = 30 , \mathrm { r } = 3 , \mathrm {~L} = 20 \text {. Tube two: } \Delta \mathrm { P } = 60 , \mathrm { r } = 4 , \mathrm {~L} = 10$$

Accepted Answer

The answer of Compare the flow rates (Q)of tubes one...

Question 8

Drugs known as calcium channel blockers can be used to

Accepted Answer

A)  decrease the force of cardiac contraction. 
B)  increase blood pressure. 
C)  constrict the coronary arteries. 
D)  increase sympathetic stimulation of the myocardium. 
E)  increase stroke volume.

Question 9

Listening to the heart through the chest wall is called ________.

Accepted Answer

The answer of Listening to the heart through the chest...

Question 10

The AV node is important because it

Accepted Answer

A)  directs electrical impulses from the ventricles to the atria. 
B)  delays the transmission of the electrical impulses to the ventricles in order for the atria to finish contracting. 
C)  serves as the pacemaker in a normal heart. 
D)  electrically opens the AV valves. 
E)  None of these answers are correct.

Question 11

In the condition known as complete heart block, what happens?

Accepted Answer

A)  Coronary arteries are blocked by plaques, preventing blood and oxygen from reaching the myocardial contractile cells. 
B)  Electrical signals from the SA node never reach the ventricles, so the contraction of the atria is not coordinated with the contraction of the ventricles. 
C)  The fibrous skeleton of the heart breaks down, interfering with the passage of blood from the atria to the ventricles. 
D)  The mitral valve leaflets calcify and close, preventing blood from being pumped efficiently by the left side of the heart. 
E)  Blood flow through the foramen ovale is blocked.

Exam 14: Cardiovascular Physiology

In which of the following situations would the end-systolic volume (ESV) be the greatest?