Which of the Following Events in Muscle Contraction Is the First

question 11

Multiple Choice

Which of the following events in muscle contraction is the first to occur chronologically?

• A) The T-tubules depolarize, causing calcium to be released from the sarcoplasmic reticulum.
• B) Calcium is resequestered (taken up) into the sarcoplasmic reticulum.
• C) Tropomyosin moves, exposing the actin active sites.
• D) The innervating alpha-motor neuron has an action potential.
• E) The binding of acetylcholine causes a skeletal sarcolemma to have an action potential.

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Definitions:

Protons

Positively charged subatomic particles found within the nucleus of an atom.

Magnetic Field

A field produced by electric currents or magnetic materials that exerts a force on other currents and magnetic materials.

Electrons

Subatomic particles with a negative charge, involved in chemical bonding and electricity.

Cells

The basic structural, functional, and biological unit of all known living organisms, consisting of cytoplasm enclosed within a membrane.