ecg

Question 1

cardiac muscles can conduct nervous impulses known as

Answer 1

action potentials

Question 2

what value is given to resting membrane potential

Answer 2

-90mv

Question 3

define depolarisation

Answer 3

response in muscle cells causing contraction- one cell can stimulate a wave of adjoining cells to contract

Question 4

define repolarisation

Answer 4

the depolarised cell returning to resting potential and getting ready for next contraction

Question 5

what are the 3 phases of an ECG

Answer 5

p phase, QRS phase and T phase

Question 6

what occurs at p phase

Answer 6

arterial depolarisation

Question 7

what occurs at the QRS phase

Answer 7

ventricular depolarisation

Question 8

what occurs at the t phase

Answer 8

ventricular repolarisation

Question 9

when does arterial repolarisation occur

Answer 9

also during QRS complex but too small to be noticeable compared to the ventricular depolarisation

Question 10

explain the 6 stages of an ECG, beginning with the p stage

Answer 10

1. p- sa node sends impulse across atria, they contract(depolarise) 2. interval- impulse stops at av node allowing for all blood to drain into ventricles 3. QRS- impulse passed onto ventricles, ventricular depolarisation occurs at apex and atrial repolarisation is complete. 4. interval- ventricular depolarisation complete and starts to repolarise. 5. T- ventricular repolarisation begins at apex 6. interval- repolarisation complete and cycle repeats with atria filling with blood and sa node ready to release impulse

Question 11

which nervous system regulates HR

Answer 11

autonomic nervous system

Question 12

if somebody is experiencing >100 bpm what would the condition be called

Answer 12

Tachycardia

Question 13

if somebody is experiencing <60 bpm what would their condition be called

Answer 13

bradycardia

Question 14

what is the common word used for myocardial infarction (MI)

Answer 14

heart attack