Cardiac Conduction System

Question 1

What is the order that impulses travel in your heart

Answer 1

S double A, double B, P, V

SAN
Atrial systole
AVN
Bundle of His
Bundle Branches
Purkinje fibres
Ventricular systole

Question 2

What does myogenic mean

Answer 2

This means that it has the ability to produce it’s own electrical impulses.

Question 3

What is the impulse that spreads across the heart called

Answer 3

Wave of excitation

Question 4

How does the cardiac system work

Answer 4

Electrical signal in SAN

Wave of excitation causes atrial systole to contract

Impulse passed to the AVN where delayed 0.1s

So atria can fully contract before ventricles, giving ventricles time to fill with blood

Then impulse goes to bundle of his where it is divided into bundle branches

Then into the purkinje fibres

Then spreads out into ventricles causing them to contract= ventricular systole

Question 5

What is the diastole phase

Answer 5

Heart relaxing filling up with blood

Atria fills with blood pressure builds

Valves slowly open

Question 6

What is the systole phase

Answer 6

Pressure has built up in the diastole phase

Atrial systole = valves forced open, atria contact push blood into ventricles

Ventricular systole = blood in ventricles, ventricles contract = increase pressure

Question 7

Long term effects of exercise

Answer 7

Increase stroke volume
Increase cardiac output
Lower resting heart rate
Decrease risk of cardiac disease
Heart muscle hypertrophy