Q. Considering conduction rates in myocardial cells, which statement is TRUE? (Solved)
1. Perkinje fibres are subepicardial and are the largest fibres, 4-7 times the width of other fibres
2. Perkinje fibres are ‘fast fibres’, and can conduct a wave of depolarisation at a speed of 4m/sec
3. the duration of the action potential and refractory period in fast fibres is shorter than slow fibres
4. initial depolarisation occurs in fast fibres with a rapid influx of Ca2+ ions from the sarcoplasmic reticulum
5. none of the above statements are true
- b. Perkinje fibres are ‘fast fibres’, and can conduct a wave of depolarisation at a speed of 4m/sec