1. DNA

2. The fingerprint that’s inside your body!!!!!!
DNA
The fingerprint that’s inside your body!!!!!!

3. You can tell people apart by their fingerprints because everyone’s are a little bit different…
DNA is like a fingerprint because everyone’s is a little different!

4. Fun DNA Facts!
DNA is too small to see, but under a microscope it looks like a twisted up ladder!
DNA stands for: D: Deoxyribose N: Nucleic A: Acid
Every living thing has DNA. That means that you have something in common with a zebra, a tree, a mushroom and a beetle!!!!

6. DNA is packed tightly in the cell
Learning Target: Describe the structure of a
DNA molecule
chromosome
DNA double
helix
Supercoils
histones

7. DNA is made up of steps and rails like a ladder.
This is a rail/side
This is a step/rung
Green can only go with Red
Purple can only go with Yellow

8. organic polymer made up of repeating nucleotides
DNA Structure:
organic polymer made up of repeating nucleotides
Nucleotide
H bonds
Sugar-phosphate
backbone
Nitrogen Bases A T C G

9. Building blocks of DNA: Nucleotides

10. The sugar = Deoxyribose
Shape = pentose
The phosphate

11. The nitrogenous bases
Purines

12. How are the pyrimidines different from the purines?
The nitrogenous bases
Pyrimidines
How are the pyrimidines different from the purines?

13. Purines =(2 Carbon rings) Pyrimidines = (1 Carbon ring)
A G C T

14. Four different Nucleotides
BASIC STRUCTURE

15. DNA is a polymer formed by base pairing: Base pairing rule
A pairs with T
C pairs with G

16. PRACTICE BASE PAIRING __________________________________
A G T C C G T T A G T
T C A G G C A A T C A

17. The Double Helix
The overall shape of DNA is described as a double helix (a twisted ladder).
What forces holds the two strands together?
Covalent Bonds
Hydrogen bonds

18. Who Discovered the DNA Structure?
Watson and Crick – 1953
Model was a rope ladder that had been given a twist = double helix

19. Where have we seen DNA being replicated?
Cell cycle MITOSIS AND MEIOSIS

20. DNA Replication 1. DNA “unzips”
Enzymes (helicases) break H bonds b/w nitrogen bases
Forming a replication fork (where the 2 strands separate)
2. Free DNA nucleotides pair up along the nitrogen bases
DNA polymerases (enzymes) make sure that the bases pair correctly
3. Bonds form
Covalent bonds form b/w sugars and phosphates
Hydrogen bonds form b/w nitrogen bases for both molecules

21. DNA Replication
Result: 2 new exact copies of original DNA molecule/ happens b/4 mitosis
See page 316 in book and animations

22. DNA Replication
ANIMATION
ANIMATION DETAILED

23. How are DNA and RNA similar?
DNA is composed of nucleotides and RNA is composed of nucleotides

24. How are DNA and RNA different?

25. How are DNA and RNA different?
Nucleotides = deoxyribose sugar
Double helix structure
Stays inside nucleus
RNA…
Nuleotides = ribose sugar
Single-strand structure
Located both inside and outside of nucleus
Uracil instead of thymine (U instead of T)

26. Enzymes involved in DNA replication
Helicase – opens the double helix to allow for replication
DNA polymerase – reads the original DNA strand and lays down complementary bases
Ligase - glues the newly formed DNA together

27. DNA replication practice
You are DNA polymerase. Helicase has opened the DNA strand – read each side and produce the complementary copies.
__________________________________
A G G T A A C C G G T T A C G A T T A T
T C C A T T G G C C A A T G C T A A T A

28. PRACTICE BASE PAIRING RULES AGAIN
__________________________________
A G T C C G T T A G T
T C A G G C A A T C A

29. Protein Synthesis= transcription and translation
DNA contains all the information for your traits – the genes
These genes are blueprints and need to remain safe – kept inside the nucleus
Copies can be made though – a messenger