DNA-STRUCTURE AND REPLICATION

2. Family Resemblances
•Why do siblings often look alike?

3. Family Resemblances
•Why do siblings often look alike?
•Why do children often look like their parents?

4. Family Resemblances
•Why do siblings often look alike?
•Why do children often look like their parents?
•Do parents physically give their offspring their
characteristics?

5. Family Resemblances
•Why do siblings often look alike?
•Why do children often look like their parents?
•Do parents physically give their offspring their
characteristics?
•How do ‘genes’ actually work?

6. Biomolecules
Four classes of biomolecules:

7. Biomolecules
Four classes of biomolecules:
1) Carbohydrates (sugars)
Glucose

8. Biomolecules
Four classes of biomolecules:
1) Carbohydrates
2) Lipids (fats)

9. Biomolecules
Four classes of biomolecules:
1) Carbohydrates
2) Lipids (fats)

10. Biomolecules
Four classes of biomolecules:
1) Carbohydrates
2) Lipids (fats)
3) Proteins
An Enzyme

11. Biomolecules
Four classes of biomolecules:
1) Carbohydrates
2) Lipids (fats)
3) Proteins
4) Nucleic Acids
DNA
RNA
ATP

12. Biomolecules
Four classes of biomolecules:
1) Carbohydrates
2) Lipids (fats)
3) Proteins
4) Nucleic Acids
Comprised of
a) sugar
b) Phosphate Group
c) A ‘Base’

13. Biomolecules
Four classes of biomolecules:
1) Carbohydrates
2) Lipids (fats)
3) Proteins
4) Nucleic Acids
Comprised of
a) sugar
b) Phosphate Group
c) A ‘Base’

14. Nucleic Acids- Introduction
•Nucleic Acids store and transmit
hereditary information
•DNA- Stores the information in a ‘genetic code’
•RNA carries the information to the protein
synthesizing machinery

15. Structure of DNA/RNA (1)
Three Components
1)Phosphate Group
2)‘Pentose Sugar’
3)Nitrogenous base

16. Structure of DNA/RNA (2)
Phosphate Group
Structure is constant

17. Structure of DNA/RNA (3)
Deoxyribose and Ribose are both 5 carbon sugars

18. Structure of DNA/RNA (4)
Deoxyribose and Ribose are both 5 carbon sugars
What is the difference between them?

19. Structure of DNA/RNA (5)
Deoxyribose and Ribose are both 5 carbon sugars
What is the difference between them?

20. Structure of DNA/RNA (6)

21. Structure of DNA/RNA (7)
Nitrogenous Bases

22. Structure of DNA/RNA (8)
You need to remember these!

23. Structure of DNA/RNA (8)

24. Structure of DNA/RNA (9)
As a unit, these
three components
make up one
monomer.

25. A Quick Aside (but an important
one)
What is a monomer?

26. A Quick Aside (but an important
one)
What is a monomer?
A monomer is an individual unit that acts
as a building block for large biological molecules
Monomers are nearly identical units

27. A Quick Aside (but an important
one)
What is a monomer?
A monomer is an individual unit that acts
as a building block for large biological molecules
Monomers are nearly identical
What is a polymer?

28. A Quick Aside (but an important
one)
What is a monomer?
A monomer is an individual unit that acts
as a building block for large biological molecules
Monomers are nearly identical units
What is a polymer?
A polymer is large molecule made up many
small monomers. Think of a chain.

29. Polymers are linked by Covalent
Bonds

30. Polymers are linked by Covalent
Bonds

31. So What?

32. So What?

33. DNA/RNA are Polymers of
Nucleotides
+ =

34. A DNA Strand!

35. Two DNA Strands!
The sequence of nitrogenous bases is the code of DNA

36. The sequence of nitrogenous bases is the code of DNA
‘Base Pairing’ Cytosine + Guanine
Adenine + Thymine

37. The sequence of nitrogenous bases is the code of DNA
‘Base Pairing’ Cytosine + Guanine
Adenine + Thymine

38. Reminder
• Purines
– Adenine (A)
– Guanine (G)
• Pyrimidines
– Cytosine (C)
– Thymine (T)
– Uracil (U)
• (In RNA only)

39. Reminder
• Purines
– Adenine (A)
– Guanine (G)
• Pyrimidines
– Cytosine (C)
– Thymine (T)
– Uracil (U)
• (In RNA only)
Pairing
Let’s come up with a pneumonic

40. The Double Helix
This shows two
strands of DNA in
the form in which
DNA is present
within cells.

41. The Double Helix
This shows two
strands of DNA in
the form in which
DNA id present
within cells.
Within all of your
cells (almost).

42. DNA Structure

43. Review
1) Name the four classes of biomolecules
Give an example of each

44. Review
1) Name the four classes of biomolecules
Give an example of each
2) Explain why offspring look like parents

45. Review
1) Name the four classes of biomolecules
Give an example of each
2) Explain why offspring look like parents
3) Define nucleotide

46. Review
1) Name the four classes of biomolecules
Give an example of each
2) Explain why offspring look like parents
3) Define nucleotide
4) Define monomer and polymer

47. Review
1) Name the four classes of biomolecules
Give an example of each
2) Explain why offspring look like parents
3) Define nucleotide
4) Define monomer and polymer
5) What are the 3 components of a
nucleotide?

48. Review
1) Name the four classes of biomolecules
Give an example of each
2) Explain why offspring look like parents
3) Define nucleotide
4) Define monomer and polymer
5) What are the 3 components of a nucleotide?
6) What is one difference between DNA and RNA?

49. Review
1) Name the four classes of biomolecules
Give an example of each
2) Explain why offspring look like parents
3) Define nucleotide
4) Define monomer and polymer
5) What are the 3 components of a nucleotide?
6) What is one difference between DNA and RNA?
7) What type of reaction occurs to allow monomers
of nucleotides to form polymers?
Draw out an example.

50. Review
1) Name the four classes of biomolecules
Give an example of each
2) Explain why offspring look like parents
3) Define nucleotide
4) Define monomer and polymer
5) What are the 3 components of a nucleotide?
6) What is one difference between DNA and RNA?
7) What type of reaction occurs to allow monomers of
nucleotides to form polymers?
Draw out an example.
8) What shape does DNA take in your cells?

51. More Review
1) Name the Purines.

52. More Review
1) Name the Purines.
2) Name the Pyrimidines.

53. More Review
1) Name the Purines.
2) Name the Pyrimidines.
3) What base pairs with Cytosine?
4) What base pairs with Thymine?