Which of the Following Events Occurs During the Lag Phase

question 69

Multiple Choice

Which of the following events occurs during the lag phase of a muscle twitch?

• A) Muscle fibers shorten.
• B) Cross-bridges form, move, release, and reform many times.
• C) The action potential is propagated from presynaptic to postsynaptic membrane.
• D) Ca²⁺ are pumped back into the sarcoplasmic reticulum.
• E) All of these events occur in the lag phase.