Question

When the action potential travels down the lumen of the t-tubules, _____ is stimulated which causes a conformational change of ___ which allows Ca to be released. When contraction stops, ____ takes up Ca and places it back into the sarcoplasmic reticulum.

Select the appropriate sequence of terms from the options below:

RyR = ryanodine receptor

DHP = Dihdropyridine receptor

SERCA = SER Ca-ATPase

Answer 1

The correct sequence is DHP,RyR,SER Ca ATPase

When the action potential travels down the lumen of the t-tubules, Dihydropyridine receptor is stimulated which causes a conformational change of Ryanodine receptor which allows Ca to be released.When contraction stops,SER Ca-ATPase takes up Ca and places it back into the sarcoplasmic reticulum.

The action potential travels down the lumen of t-tubules and stimulates Dihydropyridine receptor which senses membrane depolarization and opens the Ryanodine receptor channel on the sarcoplasmic reticulum and causes the release of Ca.Once the contraction stops Ca movement is shut off and is reuptaken back into Sarcoplasmic reticulum through SERCA.