The muscle fiber fires an action potential. on the T-tubule sense the voltage change and mechanically open ryanodine receptors (RyRs) on the sarcoplasmic reticulum. Calcium floods the cytosol.
The hose is open.
AMPA receptors open. The LMN depolarizes enough to kick out the magnesium block from NMDA receptors. Now calcium enters the LMN — a key step for , the cellular basis of motor learning. brain bee study guide