Cardiovascular - Conduction System And Cardiac Cycle

Question 1

What is the intrinsic conduction system?

Answer 1

Specialized cells that generate and transmit electrical impulses triggering contract and ensures chambers contract in synchronized manner

Basically triggers contraction and explains how it contracts

Question 2

What can affect heart rate?

Answer 2

Temperature, bp, hormones, etc

Question 3

What is the Sinoatrial (SA) node?

Answer 3

Heart’s pacemaker (heart can contract without signal from nervous system because of these pacemakers cells)

Sends signals to right and all the way to the left atrium to contract

Question 4

What is the atrioventricular (AV) bundle node?

Answer 4

Delays impulse received from SA node slightly to allow atrium to fully contract

Question 5

What is the Atrioventricular bundle node (bundle of his)?

Answer 5

Pathway that conducts electrical impulse from AV node down through the inter ventricular septum

Question 6

What are bundle branches?

Answer 6

Carry electrical impulse down interventricular septum to right and left ventricles

Question 7

What are Purkinje fibres?

Answer 7

Spread electrical impulses throughout ventricles, causing them to contract and pump blood to lungs and rest of body

Question 8

What is a electrocardiogram?

Answer 8

Records electrical activity of heart using electrodes on surface of body (ECG/EKG)

Question 9

What part of the nervous system adjusts HR? How does PNS and SNS effect heart rate?

Answer 9

Autonomic nervous system

PNS = decreases HR
SNS = increases HR

Question 10

What is the cardiac cycle?

Answer 10

Sequence of events in one heartbeat (contraction aka systole and relaxation aka dystole)

Question 11

What are the two basic phases of cardiac cycle? What occurs during these two phases?

Answer 11

Contraction - blood pushed into adjacent chambers or arterial trunk
relaxation - chamber fills with blood