Question

Question 5 1.5 pts The opening of prevent _ensures that contractile myocardial cells remain depolarred much longer than neurons or skeletal muscles during an action potential. This helps so that the heart will always relax during diastole. volgeted Natchannel bradycardia volte sted 2 channel bradycardia volt -sated 2 channels, tetanus voltated Natchastetanus

Answer 1

The opening of voltage gated Ca2+ channels ensures that contractile myocardial cells remain depolarized much longer than neurons or skeletal muscles during an action potential. This helps prevent bradycardia so that the heart will always relax during the diastolell always relax during the diastole.

Action potential of cardiac muscles Grigoriy Ikonnikov and Eric Wong Phase 4 Phase Phase 1 Phase 2 Phase 3 ECF Na + Ca2+ ICF K+ K+ K+ Transient K+ channels open and K+ efflux returns TMP to OmV 1 Rapid Na+ influx through open fast Na+ channels Membrane potential (mV) Influx of Ca2+ through L-type Ca2+ channels is electrically balanced by K+ efflux through delayed rectifier K+ channels 3 Ca2+ channels close but delayed rectifier K+ channels remain open and return TMP to -90mV Na+, Ca2+ channels closed, open K+ rectifier channels keep TMP stable at -90mV -90 -100 Time