Cardiac myocytes (contractile cells) have a prolonged action potential including a plateau phase which lasts up...

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Cardiac myocytes (contractile cells) have a prolonged actionpotential including a plateau phase which lasts up to ~250ms. Thisis to enable a longer, sustained contraction so that the ventricleshave time to pump blood out. In order to enable this â€˜plateauâ€™phase (Phase 2):
Group of answer choices
Slow Na⁺ channels enable a sustained inwardNa⁺ current.
Slow K⁺ channels enable a sustained inwardK⁺ current, balance with Na⁺ efflux.
L-type Ca²⁺ channels enable Ca²⁺ influxwhich is balanced by a slight K⁺ efflux.
Only Na⁺ and K⁺ are involved in thisaction potential, just like a neuron, only it takes longer for thevoltage-gated K⁺ channels to open and repolarise thecell.

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Option CLtype Ca2 channels enable Ca2 influx which is balanced by a slight K efflux Phase 2 is the plateau phase of the cardiac action potential A plateau phase occurs during which Ca 2 enters the cytosol of the muscle cell Ca 2 enters from the sarcoplasmic reticulum See Answer

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