1. What is DNA? Instructions for making proteins
‘Blueprint’ for who we are
Where is it found?
Found in the nucleus
What does ‘DNA’ stand for?
Deoxyribonucleic Acid

2. The Structure of DNA
Double helix
Structure of DNA: Twisted Ladder

3. Who Discovered DNA’s Structure?
SCANDAL! Read all about it!
Rosalind Franklin, James Watson, Francis Crick, & Maurice Wilkins discovered the shape (double helix) of DNA is 1953.

4. DNA is a polymer of Nucleotides. What are the 3 parts of a nucleotide?
THINK!
DNA is a polymer of Nucleotides.
What are the 3 parts of a nucleotide?

5. Nucleotides
DNA Subunit
3 components
a sugar
a phosphate group
a nitrogen base

7. Nitrogen Bases 4 Types: Adenine Thymine Guanine Cytosine REMEMBER:
At The Golf Course

8. Complementary Base Pairs
Nitrogen bases always pair with the same partner
Hydrogen bonds hold the bases together.
A--T (At--The)
G--C (Golf--Course)

9. THINK! What would the complementary strand be?
A-T-C-C-G-T-T-T-A-C-A-G-G-A
T-A-G-G-C-A-A-A-T-G-T-C-C-T

10. DNA Review

11. DNA is the instructions for making what?

12. Protein

13. What type of biomolecule is DNA?

14. Nucleic Acid

15. What type of sugar is in DNA?

16. Deoxyribose or pentose

17. Draw and name the shape of dna

18. Double Helix

19. Who took credit for discovering dna?

20. Watson and Crick

21. Who actually discovered dna?

22. Rosalind Franklin

23. What is a polymer?

24. A long chain of repeating units (subunits)

25. What is the subunit of DNA?

26. Nucleotide

27. Sugar, phosphate and ___________ make up a nucleotide.

28. Nitrogen Base

29. Adenine, ________, cytosine, and __________ are the 4 nitrogen bases of dna

30. Thymine and guanine

31. Thymine pairs with ___________

32. Guanine pairs with __________

33. Write the complimentary stand: C – G – T – A

34. G - C – A – T

35. Write the complimentary strand: g – g – t – a – t – a

36. Write the complimentary strand: a – a – t – g – c

37. Write the complimentary strand: c – t – a – t – g

38. Nucleotides join to form long chain (polymer) Sides of the ladder:
How DNA Strands Form
Nucleotides join to form long chain (polymer)
Sides of the ladder:
Sugar + Phosphate
Rungs of ladder:
Nitrogen bases bond together

39. How is DNA Organized?
Histone proteins act like spools that wind up DNA to keep it organized.

40. During Interphase…
How does DNA exist?
Unwound! (Chromatin)

41. Why Chromatin? What happens during Interphase?
DNA Replicates!
DNA is uncoiled so that enzymes can unzip it.
When it is unzipped, DNA can be duplicated.

42. DNA Replication
Process by which DNA is copied
Occurs before mitosis and meiosis (during interphase!)

43. How DNA Duplication Occurs
Step 1: The Helicase enzyme unzips the DNA strand T A G C
HELICASE

44. Step 2: The DNA Polymerase enzyme attaches free floating nucleotides to the exposed nitrogen bases

45. Result: 2 Complete Strands!G C

46. DNA Polymerase
Replication Fork
Original Strand
Helicase
New Strand

47. Semiconservative Replication: one of the original strands is present in each new strand of DNA.

48. The Central Dogma
DNA RNA Proteins