ch 19 practice exam pt 2

Question 1

electrical signals pass between cardiomyocytes through the

Answer 1

gap junctions

Question 2

the _____ is the pacemaker that initiates each heart beat

Answer 2

sinuatrial (SA) node

Question 3

which of the following is NOT part of the cardiac conduction system

Answer 3

tendinous cords

Question 4

if the sinuatrial (SA) node is damaged the heart will likely beat at _____ bpm

Answer 4

40-50

Question 5

repolarization of a ventricular cardiomyocyte takes longer than repolarization of a typical neuron

Answer 5

true

Question 6

any abnormal cardiac rhythm is called

Answer 6

arrhythmia

Question 7

atrial systole begins

Answer 7

during P wave

Question 8

atrial depolarication causes the

Answer 8

P wave

Question 9

in a normal ECG the deflection that is generated by ventricular depolarization is called the

Answer 9

T wave

Question 10

blood pressure is usually measured in millimeters of mercury (mmHg) but could be measured with any liquid such as water (mm H2O)

Answer 10

true

Question 11

papillary muscles prevent the AV valves from prolapsing (bulging) excessively into the atria when the ventricles contract

Answer 11

true

Question 12

when the left ventricle contracts the ____ valve closes and the ______ valve is pushed open

Answer 12

mitral; aortic

Question 13

when the ventricles relax the ___ valve prevents backflow of blood into the left ventricle

Answer 13

aortic

Question 14

mitral valve prolapse (MVP) generated a murmur associated with the _____ heart sound that occurs when the ______

Answer 14

lubb (S1); ventricles contract

Question 15

when the aortic semilunar valve closes and blood bounces off of it, it produces the ______ heart sound that is ultimately related to when the ______

Answer 15

dupp (S2); ventricles relax

Question 16

during isovolumetric contraction the pressure in the ventricles ____

Answer 16

rises rapidly

Question 17

what is the correct sequence events of the cardiac cycle

Answer 17

• ventricular filling
• isovolumetric contraction
• ventricular ejection
  isovolumetric relaxation

Question 18

congestive heart failure (CHF) of the right ventricle

Answer 18

can cause systemic edema

Question 19

isovolumetric contraction occurs during the ____ of the ECG

Answer 19

R wave

Question 20

the ventricles are almost empty at the end of ventricular diastole

Answer 20

false

Question 21

ventricular pressure increases the fastest during ventricular filling

Answer 21

false

Question 22

most of the ventricle filling occurs

Answer 22

during atrial diastole

Question 23

assume that the left ventricle of a child’s heart has an EDV=90mL and ESV=60mL and a cardiac output of 2,400 mL/min.
his SV is _____ mL/beat and his HR is _____ bpm

Answer 23

30; 80

Question 24

the volume of blood ejected by each ventricle in 1 min is called the

Answer 24

cardiac output

Question 25

stroke volume is increased by

Answer 25

increased venous return

Question 26

hypercapnia and acidosis have pos chronotropic effects

Answer 26

true

Question 27

cardioinhibitory centers in the _____ receive input from _____

Answer 27

medulla oblongata; chemoreceptors in the aortic arch

Question 28

the frank-starling law of the heart states that stroke volume is proportional to

Answer 28

the end-dialostic volume

Question 29

under normal condiitons the amount of blood pumped through the pulmonary circuit is less than the amount pumped through the systemic circuit

Answer 29

false

Question 30

endurance atheletes commonly have a resting heart rate as low as 40 bpm and a stroke volume as low as 50 mL/beat

Answer 30

false

Question 31

match the heart sound with the action or event believed to cause it

Answer 31

1. 1st heart sound (S1)
2. 2nd heart sound (S2)
3. 3rd heart sound (S3)