Lecture 9

Question 1

Are electrical cells low or high in actin and myosin and why?

Answer 1

Low- don’t contract

Question 2

Where in the heart does depolarisation start?

Answer 2

Sinoatrial node ( SA) node

Question 3

Describe the path of electrical impulse in the heart/

Answer 3

starts at sinoatrial node ( pacemaker) and travels to:
- right atrium
- left atrium ( through interatrial bundle and fibres)
- Atrioventricular node ( AV node)
Atrioventricular node pauses signal then sends it to:
- Right and left ventricle septum ( AV bundle branches)
- right and left lateral wall ( purkinje fibres)

Question 4

What is a lead in an ECG?

Answer 4

Virtual line between two surface electrodes that detects a difference between electrodes

Question 5

What does the P wave on an ECG represent?

Answer 5

Atrial depolarisation

Question 6

What does the QRS complex

Answer 6

Ventricular depolarisation

Question 7

What does the T was of a ECG represent?

Answer 7

Ventricular repolarisation