Describe the basic sequence of events that occurs as an action ...

[tiffannnnyyyyyy]

Describe the basic sequence of events that occurs as an action potential arrives at the neuromuscular junction and is transmitted to the muscle cell.

Question 2

Which of the following is true about the difference between cardiac muscle cells and skeletal muscle cells?
 A) Cardiac muscle cells does not have striations like skeletal muscle cells.
  B) Cardiac muscle cells does not have t-tubules.
  C) Cardiac muscle cells does not have sarcomeres.
  D) Cardiac muscle cells have intercalated discs where skeletal muscle cells do not.
  E) Cardiac muscle cells have more nuclei in them than skeletal muscle cells.

[cpetit11]

Answer to Question 1

The action potential triggers the exocytosis of neurotransmitters stored in vesicles in the axon terminal. This acetylcholine binds to receptors in the motor end plate, increasing the muscle membrane permeability to sodium. Acetylcholinesteras e destroys the acetylcholine, ensuring that each nerve action potential produces only a single twitch. The influx of these positive sodium ions triggers an action potential. The action potential spreads in both directions away from the motor end plate across the entire surface of the muscle fiber and into the interior via transverse tubules, triggering a pulse of calcium ion release from the sarcoplasmic reticulum, which generates a brief small twitch. With additional stimuli, calcium ion builds up and higher tensions are produced.

Answer to Question 2

D

[tiffannnnyyyyyy]

TY

[cpetit11]

You're welcome