1. Discovering DNA
@babrahaminst

2. Learning Outcomes All students will:
Be able to draw the double-helix structure of DNA
Most students will:
Be able to explain what DNA is
Some students will:
Be able to list what DNA does, where it was discovered, and why scientists do research around DNA
Key word/s
DNA, experiment, structure, genetics

3. What is DNA? DNA stands for DeoxyriboNucleic Acid
It is a set of instructions or a ‘recipe’ for every living thing
How to make an elephant
DNA
CC images:
Elephant -
Recipe card -

4. What does it do? DNA contains genes Genes determine what you look like
Hair and eye colour
Height
Blood type
They are inherited from your parents
CC image:
Family -

5. DNA - who, when and where? Watson and Crick (1953) In Cambridge
But don’t forget Rosalind Franklin!
CC images:
Cambridge -
Rosalind Franklin -

6. What does DNA look like?
The DNA molecule looks like a twisted ladder, or a spiral staircase
Its shape has a special name – a ‘double helix’
CC image
DNA GIF

7. What does DNA contain? Four chemical units
Adenine (A)
Guanine (G)
Thymine (T)
Cytosine (C)
A ‘spine’ of sugar and phosphates
CC -

8. ? Where is it found? In practically every cell in your body CC images
Skeleton -
Muscle –
Circulatory system –
Nervous system -

9. Where is it found? …in your body …in cells …in the nucleusCC
Human DNA -
Chromosomes -
….in chromosomes
…is DNA!

10. How big is it?
If all 46 chromosomes from a human cell were uncoiled and placed end to end, the DNA would be:
2 metres long
2 billionths of a metre wide CC
Chromosomes -

11. How much DNA do we have? …over 800 times!
If the DNA from every cell in your body was put end to end, it would reach to the moon and back…
…over 800 times!
CC:
Moon -

12. 50% 99.9% 98% How similar are you to…. …a banana? …me?
Add picture here
99.9% CC
Banana -
Chimpanzee -
…a chimpanzee?
98%

13. Why learn about DNA? Some diseases are caused by faulty DNA
Gene transfer helps to make proteins, such as the one that makes blood clot
Genetically-modified (GM) crops can resist pest attacks or weed-killers

14. Activity: DNA sweets
Follow instructions to make your own models of DNA using sweets
See recipe sheet for instructions

15. Recap What does DNA look like?
Who discovered the shape of the DNA molecule?
Where was the discovery announced?
And when?
What is in the DNA molecule?
Where is DNA found?
Where do you get your DNA from?
What does DNA do?
How similar is human DNA to banana DNA?
How similar is human DNA to monkey DNA?
How similar is your DNA to my DNA?