Muscle contraction is regulated by:
A. depletion of acetylcholine, which returns
the ligand-gated ion channel to the resting,
closed conformation, preventing further
transport of sodium ions.
B. an ATP-powered sodium pump in the
plasma membrane that continuously works to
set up a sodium concentration gradient.
C. an enzyme that degrades and removes
acetylcholine from the neuromuscular
junction.
D. the resting neuron that does not release
acetylcholine into the neuromuscular junction.
E. All of these choices are correct.
E
You might also like to view...
Streptococcus pneumoniae is a bacterium that has long been recognized as a major pathogen
causing pneumonia. Based on its name, how might it look under a microscope?
a. Because it is a bacterium, it will be very small and difficult to distinguish. b. It would look like a chain of round beads or balls. c. It would be about the size of a eukaryotic cell. d. both (b) and (c)
In which stage of labor dose the amniotic sac rupture?
a. the first stage b. the second stage c. the third stage d. in either the first or second stage e. in either the second or third stage
The veins leading from the lungs to the heart are the ________ veins.
Fill in the blank(s) with the appropriate word(s).
What structure prevents food from entering the larynx?
A) Respiratory membrane B) Intercostal muscle C) Epiglottis D) Diaphragm E) Bronchus