1. KEY CONCEPT DNA replication copies the genetic information of a cell.

2. Replication copies the genetic information.
A single strand of DNA serves as a template for a new strand.
The rules of base pairing control replication.
DNA is replicated during the S (synthesis) stage of the cell cycle.
Each body cell gets a complete set of identical DNA.

3. Proteins carry out the process of replication.
DNA serves as a template.
Enzymes and other proteins do the actual work of replication.
Enzymes unzip the double helix.
Free-floating nucleotides form hydrogen bonds with the template strand.
nucleotide
The DNA molecule unzips in both directions.

4. DNA polymerase enzymes bond the nucleotides together to form the double helix.
Polymerase enzymes form covalent bonds between nucleotides in the new strand.
DNA polymerase
new strand
nucleotide

5. DNA replication is semiconservative.
Two new molecules of DNA are formed, each with an original strand and a newly formed strand.
DNA replication is semiconservative.
original strand
new strand
Two molecules of DNA

6. Replication is fast and accurate.
DNA replication starts at many points in eukaryotic chromosomes.
There are many origins of replication in eukaryotic chromosomes.
DNA polymerases can find and correct errors.

7. The process that makes an exact copy of a cell’s DNA is called
Conservation
Preservation
Replication
Synthesis

8. What are the main functions of DNA polymerase?
Breaks down hydrogen bonds and exposes bases
Holds DNA strands apart and attracts bases
Zips and unzips the double-stranded DNA
Binds nucleotides and corrects base pair errors

9. Which of the following events occurs directly after a DNA molecule is unzipped?
Mismatched nucleotides bases are identified and replaced
Free-floating nucleotides pair up with exposed bases
Identical double stranded DNA molecules are formed
Enzymes break down hydrogen bonds between base pairs

10. The process of making new DNA molecules is semiconservative
The process of making new DNA molecules is semiconservative. This means that every new DNA molecule is composed of
Two completely identical strands of DNA
One original and one new strand of DNA
One strand of DNA and one strand of RNA
Two strands that mix original and new DNA

11. When new DNA molecules are formed, almost all errors are detected and fixed by
The correct nucleotide
The sugar-phosphate backbone
DNA polymerase
One DNA strand