Electrical activity of heart

Question 1

Period of contraction, force generation and blood expulsion

Answer 1

Systole

Question 2

Period of relaxation, filling with blood, readying for next systole

Answer 2

Diastole

Question 3

Left atrial fibrillation would most greatly affect filling of which other heart chamber?

Answer 3

Left ventricle

Question 4

This is the first to depolarize, and is located in right atrium. What does it do?

Answer 4

SA node, pacemaker which causes atrial contraction

Question 5

True/False: there are gap junctions between an atrial muscle to a ventricle muscle.

Answer 5

False, there are NONE, no comunication

Question 6

A lot of arrhythmia are due to a problem in the________.

Answer 6

AV node

Question 7

AV node ____ conduction.

Answer 7

Slows

Question 8

_______ has large diameter cells and speeds up ventricular myocytes.

Answer 8

Perkinje system

Question 9

With ventricular myocytes ________ occurs.

Answer 9

contraction

Question 10

What is the flow of depolarization?

Answer 10

SA node fires
Atria depolarize
Septum and inner layer of ventricular muscle depolarizes
Ventricles depolarize
Coordination of depolarization allows for maximal blood ejection.

Question 11

How does depolarization start in heart?

Answer 11

Starts at apex in Inter-ventricular septum depolarizes first and then depolarization wave heads up towards atrium

Question 12

SA node is the pacemaker of the heart because why?

Answer 12

it depolarizes the fastest

Question 13

When something has a firing rate faster than the SA node what is this called? and why can this happen?

Answer 13

Ectopic pacemaker
SA node slows
Ectopic is faster
(can live off of AV node)