View the animation below, then complete the quiz to test your knowledge of the concept.

1	When the acetylcholine receptor sites are not occupied...
	A)	a ligand is formed.
	B)	the sodium channels open.
	C)	the sodium channels remain closed.
	D)	sodium ions diffuse through and enter the cell.
	E)	sodium ions diffuse through and leave the cell.
2	When the acetylcholine binds to the receptor sites...
	A)	a ligand is formed.
	B)	the sodium channels open.
	C)	the sodium channels remain closed.
	D)	sodium ions diffuse through and enter the cell.
	E)	sodium ions diffuse through and leave the cell.
3	Which causes...
	A)	a ligand to be formed.
	B)	the sodium channels to open.
	C)	the sodium channels close.
	D)	sodium ions to diffuse through and enter the cell.
	E)	sodium ions to diffuse through and leave the cell.
4	The sodium channels in the cell membrane have receptor sites for acetylcholine.
	A)	True
	B)	False
5	This channel is formed by a channel protein.
	A)	True
	B)	False