13. Describe the basic sequence of events that occurs as anaction potential arrives at the neuromuscular junction and istransmitted to the muscle cell and leads to a contraction. Explainat the end how relaxation of the muscle takes place (include whathappens at the neuromuscular junction and in the muscle fiber. Youmay use some words multiple times. Fill in the blanks with acomplete word or words (no abbreviations) of each step.

1. An action potential arrives at the synaptic bulb of a motorneuron causing the exocytosis of vesicles containing ___

2. ____ diffuses across the synaptic cleft to bind to a receptoron the ___ allowing sodium to influx resulting in an actionpotential.

3. The action potential will spread down the ___ into the centerof the muscle fiber.

4. The excitation cause the release of _____ from the ____ intothe sarcoplasm.

5. ____ will bind to ___ causing a conformational change.

6. ____ will move___ off the____ of the protein .

7. The ____ will bind to the ____ forming a ____ .

8. The ____ will ___ pulling the ___ . This is called the___.

9. ____ will attach to the ___causing it to ___from the____.

10. __ of__ provides the energy to cause the___ of the ___.

11. _____- write out the whole step

Relaxation.

___ cleaves ___

The ___ re-uptakes the ___

___ recovers the so that ___ can no longer bind.