Cardiovascular

Question 1

The region between the two pleural cavities that contains the heart and great vessels is called the ___.

Answer 1

mediastinum

Question 2

Which layer of pericardium touches the heart?

Answer 2

visceral pericardium

Question 3

Cardiac muscle tissue cells have ____.

Answer 3

intercalated discs

Question 4

Why is the left ventricle more muscular than the right ventricle?

Answer 4

It contracts with force sufficient to push blood through the systemic circuit

Question 5

Where is the ANS headquarters for cardiovascular control?

Answer 5

medulla oblongata

Question 6

What is the importance of the 100-msec delay at the AV node?

Answer 6

Atria must contract to fill the ventricles with blood

Question 7

Why is resting HR somewhat slower than the 80-100 bpm set by the SA node?

Answer 7

Parasympathetic effects dominate in a resting individual

Question 8

How is cardiac output (CO) calculated?

Answer 8

CO mL/min = (EDV - ESV) x HR

CO mL/min = HR bpm x SV mL/beat

Question 9

During ventricular systole of the cardiac cycle, all of the following would occur EXCEPT ____.

Answer 9

pressure in ventricles would force the semilunar valves closed

Question 10

When during the cardiac cycle do ventricles contain their maximal amount of blood? What is this quantity called?

Answer 10

• at the end of atrial systole; EDV

- at the end of ventricular diastole; EDV

Question 11

On an ECG reading, what does the P wave indicate?

Answer 11

atrial depolarization

Question 12

What event is taking place during the Q-T interval?

Answer 12

a single cycle of ventricular depolarization and repolarization

Question 13

What factor could cause an increase in the size of the QRS complex of an electrocardiogram recording?

Answer 13

an increase in heart size

Question 14

What condition contributes to a reduction in the size of the T wave?

Answer 14

coronary ischemia

Question 15

Why is there no wave corresponding to atrial repolarization on an ECG reading?

Answer 15

It is masked by the QS complex

Question 16

What affects the rate of venous return?

Answer 16

cardiac output, stroke volume, and heart rate

Question 17

How is eversion of the AV valves and backflow of blood into the atria prevented?

Answer 17

tightening of chordae tendineae and contraction of papillary muscles

Question 18

Doris was born with a malformed pulmonary valve. How will that affect her circulation?

Answer 18

Blood will flow back into her right ventricle

Question 19

Grandpa has developed a radiating pain in his chest upon raking leaves. What medication might be given to offer prompt relief?

Answer 19

nitroglycerin, which is a vasodilator of coronary vessels

Question 20

How does damage to the cardioinhibitory center of the medulla affect heart rate? Why?

Answer 20

Heart rate increases; sympathetic dominance

Question 21

What blood vessels bring blood back into the right atrium?

Answer 21

superior and inferior venae cavae and coronary sinus

Question 22

What is the effect of NE binding to adrenergic receptors?

Answer 22

increases vasoconstriction and increases heart rate

Question 23

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?

Answer 23

60%

Question 24

Frank has just run a marathon and his heart is beating extremely rapidly. What happens to the length of diastole and filling time?

Answer 24

both decrease

Question 25

Why is ESV lower when you are actively exercising?

Answer 25

EDC increases and ventricular muscle produces more forceful contractions ejecting more blood

Question 26

What is the most important factor in considering cardiac function over time?

Answer 26

cardiac output