Cardio 2

Question 1

Cardiac AP originates in…

Answer 1

a group of cells in the SA node (pacemaker) and spreads through autorythmic cells

Question 2

What sets the heart rate?

Answer 2

The group of autorhythmic cells with the most rapid pacemaker activity

Question 3

Backman’s bundle

Answer 3

conducts action potentials from the SA pacemaker into the left atrium, causing contraction

Question 4

Anterior, middle and posterior internodal pathways

Answer 4

conduct the AP from the SA node to the AV node, depolarizing right atrial muscle along the way

Question 5

Ventricular muscles have a spiral arrangement that ensures…

Answer 5

blood is squeezed upward from the apex of the heart

Question 6

ECG or EKG

Answer 6

electrocardiogram; represents the summed electrical activity of all cells of the heart

Question 7

Einthoven’s triangle

Answer 7

a hypothetical triangle created around the heart when electrodes are placed on both arms and the left leg

Question 8

upward deflection

Answer 8

the current flow vector is toward the positive electrode

Question 9

downward deflection

Answer 9

current flow vector is toward the negative electrode

Question 10

no deflection

Answer 10

electrical activity moving perpendicular to axis of electrodes

Question 11

waves

Answer 11

appear as deflections above or below the baseline

Question 12

segments

Answer 12

sections of baseline between two waves

Question 13

intervals

Answer 13

combination of waves and segments

Question 14

P wave

Answer 14

atrial depolarization

Question 15

P-R segment

Answer 15

conduction through AV node and AV bundle

Question 16

QRS complex

Answer 16

ventricular depolarization

Question 17

T wave

Answer 17

ventricular repolarization