Chapter 19 test

Question 1

The cardiac conduction system includes all of the following except
A. the SA node
B. the AV node
C. the bundle branches
D. the tendinous cords
E. the Purkinje fibers

Answer 1

D. the tendinous cords

Question 2

To get from right atrium to the right ventricle, blood flows through
A. the pulmonary valve
B. the tricuspid valve
C. the bicuspid valve
D. the aortic valve
E. the mitral valve

Answer 2

B. the tricuspid valve

Question 3

Assume that one ventricle of a child’s heart has an EDV of 90mL, an EVS of 60mL, and a CO of 2.55L/min. What are the child’s SV, ejection fraction (EF) and HR?
A. SV=60mL, EF=33%, HR=85bpm
B. SV=30mL, EF=60%, HR=75bpm
C. SV=150mL, EF=67%, HR=42bpm
D. SV=30mL, EF=33%, HR=85bpm
E. Not enough information is given to calculate these.

Answer 3

D. SV=30mL, EF=33%, HR=85bpm

Question 4

A HR of 45 bpm and an absence of P waves suggests
A. damage to the SA node
B. ventricular fibrillation
C. cor pulmonale
D. extra systole
E. heart blcok

Answer 4

A. damage to the SA node

Question 5

There is/are\_\_\_\_\_\_\_\_\_ pulmonary vein(s) emptying into the right atrium of the heart.
A. no
B.1
C.2
D.4
E. more than 4

Answer 5

A. no

Question 6

The coronary blood vessels are part of the circuit of the \_\_\_\_\_\_\_\_\_ circulatory system.
A. cardiac
B. pulmonary
C. systematic
D. systemic
E. cardiovascular

Answer 6

D. systemic

Question 7

The atria contract during 
A. the 1st heart sound
B. the 2nd heart sound
C. the QRS complex
D. The PQ segment
E. the ST segment

Answer 7

D. The PQ segment

Question 8

Cardiac muscle does not exhibit tetanus because it has
A. fast CA2+ channels
B. scanty sarcoplasmic reticulum
C. a long absolute refractory period
D. electrical synapses
E. exclusively aerobic respiration

Answer 8

C. a long absolute refractory period

Question 9

The blood contained in a ventricle during isovolumetric relaxation is
A. the end-systolic volume
B. the end-diastolic volume
C. the stroke volume (SV)
D. the ejection fraction
E. none of these; the ventricle is empty then.

Answer 9

A. the end-systolic volume

Question 10

Drugs that increase the HR have a \_\_\_\_\_\_\_ effect.
A. myogenic
B. negative inotropic
C. positive inotropic
D. positive chronotropic
E. negative chronotropic

Answer 10

E. negative chronotropic

Question 11

The blood supply to the myocardium is the coronary circulation; everything else is called the systemic circuit. T or F

Answer 11

False=

The coronary circulation is part of the systemic circuit; the other division is the pulmonary circuit.

Question 12

There are no valves at the point where venous blood flows into the atria. T or F

Answer 12

True

Question 13

No blood can enter the ventricles until the atria contract. T or F

Answer 13

False=
The 1st 2/3s of ventricular filling occurs before the atria contract. The atria add only about 31% of the blood that fills the ventricles.

Question 14

The vagus nerves reduce the HR but have little effect on the strength of ventricular contraction. T or F

Answer 14

True

Question 15

A high blood CO2 lever and low blood pH stimulate an increase in HR. T or F

Answer 15

True

Question 16

The 1st heart sound occurs at the time of the P wave of the electrocardiogram. T or F

Answer 16

False=

The 1st sound occurs at the time of the QRS complex.

Question 17

If all nerves to the heart were severed, the heart would instantly stop beating. T or F

Answer 17

False=

The heart has its own internal pacemaker and would continue beating; the nerves only alter the HR.

Question 18

If the 2 pulmonary arteries were clamped shut, systemic edema would follow. T or F

Answer 18

True

Question 19

Ventricular cardiocytes have a stable resting membrane potential but myocytes of the SA node do not. T or F

Answer 19

True

Question 20

An electrocardiogram is a tracing of the action potential of a cardiocyte.

Answer 20

False=
The ECG is a composite record of the electrical activity of the entire myocardium, not a record from a single myocyte. it looks much different from an action potential.