Cardiovascular

Question 1

Electrical activity of heart

Answer 1

• cardiac muscle cells
• the intrinsic conduction system
• pacemaker potentials
• cardiac muscle action potentials

Question 2

striated (contains actin and myosin) and branching

Answer 2

cardiac muscle cells

Question 3

mechanically hold cells together as heart contracts

Answer 3

desmosomes

Question 4

electrically connect cells

Answer 4

gap junctions

Question 5

intercalated discs contain two types of membrane junctions:

Answer 5

desmosomes and gap junctions

Question 6

primary pacemaker of the heart, 70-80 action potentials per minute

Answer 6

SA node

Question 7

2nd fastest node, 40-60 action potential per minute

Answer 7

AV node

Question 8

heart depolarization and repolarization is measured by an

Answer 8

electrocardiogram

Question 9

av node send signals to purkinje fibers

Answer 9

qrs complex

Question 10

relaxation phase of the chamber

Answer 10

repolarization

Question 11

this is important for creating a long refractory period

Answer 11

plateau phase

Question 12

bradycardia (slow heart beat)

Answer 12

<60 bpm

Question 13

tachycardia

Answer 13

(>100 bpm)

Question 14

irregular chaotic twitching of the myocardium

Answer 14

fibrillation

Question 15

heart is contracting and pumping blood from the heart

Answer 15

systole

Question 16

a relaxed chamber and heart muscles

Answer 16

diastole

Question 17

closing of semilunar valves closing cause the dup sound

Question 18

both vales are closed, no volume changes in ventricles

Answer 18

isovolumetric relaxation

Question 19

total blood volume

Answer 19

5-5.5 L

Question 20

average cardiac output

Answer 20

5L/min

Question 21

Heart depolarizarion and repolarization is measured by a

Answer 21

ECG (elevtrocardiogram)

Question 22

SA node to atrial depolarization

Answer 22

P-wave

Question 23

Av ode to purkinje fibres, ventricular depolarization

Answer 23

QRS complex

Question 24

Ventricular repolarization

Answer 24

T-wave

Question 25

20-40 action potnetials per minute

Answer 25

Bundle of His and Purkinje fibers

Question 26

The AV nodal delay is due to fibrous tissue. therefore, slow conduction, what is its ms

Answer 26

100 ms