1. DNA and the Structure of Proteins Section a: What is DNA?
National 5 Biology
DNA and the Structure of Proteins
Section a: What is DNA?

2. Recap
On white boards write down what you can remember from S1-S4 or your own general knowledge about genetics and inheritance

3. What are we learning today?
We are learning to:
State what DNA is
Describe the structure of DNA
The purpose of DNA
Success Criteria:
Double helix
Number of bases
Names of bases
Genetic code

4. What is DNA?
DNA clip
What is DNA?

5. What is DNA? DNA stands for Deoxyribonucleic acid
DNA is found in a cells nucleus
DNA is packaged in chromosomes
Chromosomes have areas on them that code for protein – these areas are called genes

6. What is the structure of DNA?
Double stranded (double helix)
Sugar phosphate backbone
4 bases
Adenine – A
Thymine – T
Guanine – G
Cytosine - C

7. Sugar phosphate backbone

8. 4 bases
Adenine – A
Thymine – T
Cytosine - C
Guanine – G

9. The 4 Bases The 4 bases bond in a complimentary way
Adenine always with thymine (A-T)
Guanine always with cytosine (G-C)

10. Activity Build your own molecule of DNA
Follow the instructions carefully
For Teachers - Origami DNA video instructions
If time you may get the opportunity to play the pairing game
DNA - The Double Helix