Ch 20 Flashcards
The region between the two pleural cavities that contains the heart and great vessels is called the ______.
a. mediastinum
b. visceral pericardium
c. parietal pericardium
d. pericardial cavity
a. mediastinum
Which layer of pericardium touches the heart?
a. parietal pericardium
b. pericardial sac
c. fibrous pericardium
d. visceral pericardium
d. visceral pericardium
Which of the following is true of cardiac muscle tissue?
a. Cardiac muscle cells are larger than skeletal muscle cells.
b. Cardiac muscle is not striated.
c. Cardiac muscle cells have intercalated discs.
d. Cardiac muscle cells are multin
c. Cardiac muscle cells have intercalated discs.
Why is the left ventricle more muscular than the right ventricle?
a. It pumps a larger volume of blood.
b. It contracts with force sufficient to push blood through the systemic circuit.
c. The papillary muscles are stronger.
d. Both A and B are correct.
b. It contracts with force sufficient to push blood through the systemic circuit
Where is the ANS headquarters for cardiovascular control?
a. cardiac plexus
b. SA and AV nodes
c. medulla oblongata
d. cervical and upper thoracic ganglia
c. medulla oblongata
What is the importance of the 100-msec delay at the AV node?
a. Atria must contract to fill the ventricles with blood.
b. AV valves must have time to close slowly.
c. Semilunar valves must have time to close slowly.
d. Tachycardia results if the delay is absent.
a. Atria must contract to fill the ventricles with blood.
Why is resting HR somewhat slower than the
80–100 bpm set by the SA node?
a. The AV node slows the heart to an average between its own rate and that of the SA node.
b. Parasympathetic effects dominate in a resting individual.
c. Sympathetic fibers release NE to slow heart rate.
d. Both A and B are correct.
b. Parasympathetic effects dominate in a resting individual
How is cardiac output (CO) calculated?
a. CO mL/min = (EDV – ESV) × HR
b. CO mL/min = HR bpm × SV mL/beat
c. CO mL/min = ESV/EDV
d. both A and B
d. both A and B
During ventricular systole of the cardiac cycle, all of the following would occur EXCEPT _____.
a. rising ventricular blood pressure would exceed aortic pressure
b. all heart valves would be closed
c. atrial diastole would occur as both the atria fill
d. pressure in ventricles would force the semilunar valves closed
d. pressure in ventricles would force the semilunar valves closed
When during the cardiac cycle do ventricles contain their maximal amount of blood? What is this quantity called?
a. at the end of ventricular systole; ESV
b. at the end of atrial systole; EDV
c. at the end of ventricular diastole; EDV
d. both B and C
d. both B and C
On an ECG reading, what does the P wave indicate?
a. ventricular contraction
b. an abnormal heart condition
c. atrial depolarization
d. atrial diastole
c. atrial depolarization
What event is taking place during the Q–T interval?
a. a single cycle of the cardiac cycle
b. an action potential
c. a single cycle of atrial depolarization and repolarization
d. a single cycle of ventricular depolarization and repolari
d. a single cycle of ventricular depolarization and repolarization
What factor could cause an increase in the size of the QRS complex of an electrocardiogram recording?
a. an increase in heart rate
b. a decrease in blood volume
c. a decrease in blood pressure
d. an increase in heart size
d. an increase in heart size
What condition contributes to a reduction in the size of the T wave?
a. long-term high fat intake
b. damage to the conduction pathway
c. damage to the AV node
d. coronary ischemia
d. coronary ischemia
Why is there no wave corresponding to atrial repolarization on an ECG reading?
a. It is masked by the QRS complex.
b. Atrial repolarization produces no electrical effect at all.
c. It is masked by the P wave.
d. None of the above is correct
a. It is masked by the QRS complex.
Which of the following affect(s) the rate of venous return?
a. cardiac output
b. stroke volume
c. heart rate
d. all of the above
d. all of the above
How is eversion of the AV valves and backflow of blood into the atria prevented?
a. pressure of blood pushing against the valves
b. contraction of the ventricles
c. closure of the semilunar valves
d. tightening of chordae tendineae and contraction of papillary muscles
d. tightening of chordae tendineae and contraction of papillary muscles
Doris was born with a malformed pulmonary valve. How will that affect her circulation?
a. Blood will flow more efficiently into her pulmonary trunk.
b. Blood will regurgitate into her right atrium.
c. Blood will flow back into her right ventricle.
d. Deoxygenated blood will continuously pass around her systemic circuit
c. Blood will flow back into her right ventricle.
Grandpa has developed a radiating pain in his chest upon raking leaves. Which medication might be given to offer prompt relief?
a. propranolol, which is a beta 2 blocking medication
b. nitroglycerin, which is a vasodilator of coronary vessels
c. a fibrinolytic agent to decrease hemostasis
d. none of the above
b. nitroglycerin, which is a vasodilator of coronary vessels
How does damage to the cardioinhibitory center of the medulla affect heart rate? Why?
a. Heart rate increases; sympathetic dominance.
b. Heart rate decreases; parasympathetic dominance.
c. Heart rate remains unchanged; autonomic tone makes delicate adjustments.
d. Heart rate increases; only the SA node will be controlling heart rate.
a. Heart rate increases; sympathetic dominance
Which blood vessels bring blood back into the right atrium?
a. foramen ovale, pulmonary trunk, and ductus arteriosus
b. superior and inferior venae cavae
c. superior and inferior venae cavae and coronary sinus
d. aorta, pulmonary trunk, and pulmonary veins
c. superior and inferior venae cavae and coronary sinus
What is the effect of NE binding to adrenergic receptors?
a. increases vasoconstriction
b. decreases heart rate
c. increases heart rate
d. both A and C
d. both A and C
Benjamin has an EDV of 120 mL and an ESV of 45 mL, which gives him an SV of 75 mL. What is his ejection fraction?
a. 45%
b. 75%
c. 37.5%
d. 60%
d. 60%
Frank has just run a marathon and his heart is beating extremely rapidly. What happens to the length of diastole and filling time?
a. Both increase.
b. Both decrease.
c. Length of diastole increases and filling time decreases.
d. Length of diastole decreases and filling time increases.
b. Both decrease
Why is ESV lower when you are actively exercising?
a. SV decreases and filling time increases.
b. EDV is very low and ventricular muscle is stretched very little.
c. EDV increases and ventricular muscle produces more forceful contractions ejecting more blood.
d. Parasympathetic stimulation causes it.
c. EDV increases and ventricular muscle produces more forceful contractions ejecting more blood.
What is the most important factor in considering cardiac function over time?
a. cardiac output
b. heart rate
c. stroke volume
d. end systolic volume
a. cardiac output
- Blood in the pulmonary veins will flow to which of the following locations?
a. Right Atrium
b. Right Ventricle
c. Lungs
d. Left Atrium
e. Left Ventricle
d. Left Atrium
- Contractions of the papillary muscles in the heart achieve what function?
a. Maintaining the closure of the AV valves
b. Maintaining the closure of the Semilunar valves
c. Blood ejection
d. Opening the AV valves
e. Opening the Semilunar valves
a. Maintaining the closure of the AV valves
- Which of the following is not an opening into the right atrium?
a. Coronary sinus
b. Inferior Vena Cava
c. Superior Vena Cava
d. Pulmonary Trunk
e. Tricuspid Valve
d. Pulmonary Trunk
- In a heart contraction, which of the following is the main element needed to extend the contraction time?
a. Na+
b. Cl-
c. Ca++
d. K+
e. H2SO3-
Ca++
- The Visceral Pericardium is known by another name, what is that name?
a. Myocardium
b. Endocardium
c. Metacardium
d. Epicardium
e. None of the above
Epicardium
- The EDV for a patient is 140 ml; the SV is 85, what is the ESV?
a. 65ml
b. 75ml
c. 55ml
d. 30ml
e. 225ml
55ml
- The tendonous material that holds the valves shut during ventricular systole are called what?
a. Papillary muscle
b. Pectinate muscle
c. Chordae Tendineae
d. Rugae
e. Cusps
Chordae Tendineae
- Which of the following statements is TRUE regarding the heart valves?
a. The mitral valve separates the right atrium from the right ventricle
b. The semilunar valves control blood flow returning to the heart from the body
c. The tricuspid valve separates the left atrium from the left ventricle
d. The semilunar valves have chordae tendineae and papillary muscles
e. The AV valves are supported by chordae tendineae to prevent backflow during ventricular contraction
The AV valves are supported by chordae tendineae to prevent backflow during ventricular contraction
- What is the percentage of blood filling the ventricles before the atria contract?
a. 30
b. 45
c. 50
d. 70
e. 90
70
- What is the key significance of the AV node during a cardiac cycle?
a. Serves to speed up the contraction rate
b. Acts as a braking mechanism to give the ventricles time to fill
c. Transfers the depolarization directly to the purkinje fibers
d. Produces a pace of 80-100 beats per minute
e. Is located in the superior left atrium
Acts as a braking mechanism to give the ventricles time to fill
