Cardiovascular Physiology----THE HEART AS A PUMP

Question 1

Conduction system
1. Four of the major structures that compose the conduction system of the heart are the sinoatrial node (_________________), the atrioventricular node (________________), the AV ______________, and the _________________ fibers

Answer 1

SA Node
AV Node
bundle
Purkinje

Question 2

Conduction system structures are more highly specialized than ordinary cardiac muscle tissue and permit only __________ conduction of an ____________ ______________through the heart

Answer 2

rapid

action potentials

Question 3

SA node (______________________)

a. _____________________ each heartbeat and sets its pace
b. Specialized pacemaker cells in the node possess an intrinsic ________________

Answer 3

pacemaker

initiates

rhythmn

Question 4

Sequence of cardiac stimulation
a. After being generated by the SA node, each impulse travels throughout the muscle fibers of both _____________ and the atria begin to ___________________

Answer 4

atria

contract

Question 5

As the action potential enters the ________________ from the right atrium, its conduction ____________ to allow complete contraction of both atrial chambers before the impulse reaches the ventricles

Answer 5

AV node

slows

Question 6

After the AV node, conduction velocity _____________________ as the impulse is relayed through the AV bundle into the ____________________

Answer 6

increases

ventricles

Question 7

Right and left branches of the bundle fibers and Purkinje fibers conduct the impulses throughout the muscles of both ventricles, stimulating them to contract _________________________

Answer 7

simultaneously

Question 8

ECG or EKG

Answer 8

Electrocardiogram

Question 9

Electrocardiogram is a Graphic record of the _______________________ events that precede the contractions of the heart

Answer 9

electrical

Question 10

To produce an EKG

a. _________________________ of an electrocardiograph are attached to the subject
b. Changes in voltage are recorded that represent changes in the heart’s conduction of electrical ___________________________

Answer 10

electrodes

impulses

Question 11

Normal ECG is composed of

a. P wave (represents ______________________ of the ________________________ )

Answer 11

depolarization

atria

Question 12

Normal ECG is composed of QRS complex (represents depolarization of the ______________________and repolarization of the _____________________)

Answer 12

ventricles

atria

Question 13

Normal ECG is composed of T wave (represents ______________________________ of the ventricles)

Answer 13

repolarization

Question 14

Normal ECG is composed of U wave (represents repolarization of the _________________________________ muscle)

Answer 14

papillary

Question 15

Measurement of the intervals between P, QRS, and T waves can provide information about the rate of _________________________ of an action potential through the heart

Answer 15

conduction

Question 16

The ______________ ______________ is a complete heartbeat consisting of contraction (_________________) and relaxation (_______________________) of both atria and both ventricles

Answer 16

cardiac cycle

systole
diastole

Question 17

Atrial systole

a. Contraction of _____________
b. Emptying of _____________ out of the atria into the ventricles
c. AV valves are ___________
d. _____ valves are closed
e. Ventricles are __________________ and filling with blood
f. This cycle begins with the _______ wave of the ECG

Answer 17

atria
blood
open
SL
relaxed
P

Question 18

_____________________ ventricular contraction

a. Occurs between the start of ventricular systole and the opening of the _______________________ valves

Answer 18

Isovolumetric

semi lunar

Question 19

Ventricular volume remains constant as the ________________ increases rapidly

Answer 19

pressure