Place these steps of enzyme catalysis in the correct order:
1. the substrate and enzyme change shape.
2. the substrate enters the active site.
3. the enzyme reverts to its original configuration.
4. the product is expelled.
a) 1, 2, 3, 4
b) 1, 3, 4, 2
c) 2, 1, 4, 3
d) 2, 1, 3, 4
e) 2, 3, 1, 4

Option C. 2, 1, 4, 3

Explanation:

Enzyme catalysis is defined increase in the rate of a process with the help of a biological molecule called enzyme.

Enzymes follows specific steps to perform catalysis that includes:

1) In the first step enzyme is introduced to substrate and substrate binds to the active site of enzyme and form enzyme/substrate complex.

2) In the second step the active site and substrate changes their shape. The complex holds each other together more tightly and proceed to the process of catalysis and results in enzyme/products complex.

3) After completing catalysis the enzyme releases the product.

4) After the release of enzyme, enzyme turns to its original shape or configuration.

Hence, the correct option is C.