Which process below best represents a CHEMICAL CHANGE? a
Hot water in a shower produces steam.
b
A puddle freezes over and turns to ice.
c
Aluminum foil is wrapped over a bowl of leftovers.
d
An 8th grader digests a delicious cafeteria lunch.

Choose an equation that represents an enzyme-catalyzed reaction. (a) enzyme + substrate → enzyme-substrate complex (b) enzyme + substrate ←−→ enzyme + products (c) enzyme + substrate ←−→ enzyme-substrate complex → enzyme + products (d) enzyme + substrate ←−→ enzyme-substrate complex → enzyme-substrate complex + products