How do you put these steps of DNA replication in order?

Question

1. DNA polymerase adds complementary base pairs to each strand of DNA
2. DNA polymerase "proofreads" the molecule to make sure that each molecule is a perfect copy of the original DNA.
3. DNA is "unzipped" as the hydrogen bonds between base pairs are broken and two molecules of DNA separate.

Answer 1

3--1--2:

Here's why...

In order for the base pairs to be added, the double helix structure needs to be unwrapped--this way, the DNA polymerase can "slide" into place, and insert the complimentary base pairs.

Once the addition has occured, the DNA polymerase, as a means of "proofreading" the molecule, checks that each base pair that was inserted is in fact the correct one. This keeps mutations and other random errors at a minimum.

Answer 2

3,1,2