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

1	Enzymes are
	A)	lipids.
	B)	proteins.
	C)	carbohydrates.
	D)	nucleic acids.
	E)	steroids.
2	Which of the following binds to the active site of an enzyme?
	A)	water
	B)	product
	C)	substrate
	D)	any other enzyme
	E)	none of the above
3	Which of the following correctly represents the mechanism of enzyme function?
	A)	S + P -> E-P -> E + P
	B)	E + P -> E-P -> E-S -> E + S
	C)	E + P -> E-S -> E-P -> E + P
	D)	E + S -> E-S -> E-P -> E + P
	E)	E + S -> E-P -> E-S -> E + S
4	An enzyme can only bind one reactant at a time.
	A)	True
	B)	False
5	An enzyme speeds up a chemical reaction in the cell, but can only be used once.
	A)	True
	B)	False