Biology- Science 9

Quiz on DNA

What is a Genome?

The DNA on all our chromosomes

What 3 things make up a Nucleotide?

Phosphate, Deoxyribose Sugar and a Nitrogenous base

What is the structure of DNA called?

Double Helix

What are the 4 Nitrogenous bases?

Guanine, Thymine, Adenine, Cytosine 

Which of the bases bond?

G → C and T→ A

What are the 5 steps that make identical copies of DNA?

1. Hydrogen bond breaks (unzips)

2. Free Nucleotides pair A → T and C→G

3. DNA polymerase adds Nucleotides/ enzyme

4. Ligase “glues” gaps

5. Creates a new leading strand

Why does DNA need to replicate before cells divide?

So the cells can get a complete set of genetic instructions

What does DNA polymerase do?

It prevents wrong codes from forming