1. Four Types of Macromolecules  Carbohydrates  Lipids  Proteins  Nucleic acids

2. Nucleic acids: macromolecules that store information on how to build and run a body.

3. Two Types of Nucleic Acids  Deoxyribonucleic acid (DNA)  Ribonucleic acid (RNA)  Both play central roles in directing the production of proteins.

4. Information Storage  The information in a molecule of DNA is encoded in its unique sequence of bases.  Pyrimidines: Guanine and thymine  Purines: Adenine and cytosine CGATTACCCGAT

25. DNA holds the genetic information to build an organism.

33. Base-Pairing in Double Helix  A & T  G & C  What is the complimentary strand to this strand: CCCCTTAGGAACC?

34. What is the complimentary sequence of the following strand: CCCCTTAGGAACC? 1.CCCCTTAGGAACC 2.GGGGTTAGGAACC 3.GGGGAATCCTTGG 4.GGTTCCTAAGGCC

35. If the DNA of one human cell is stretched out, it would be almost 6 feet long and contain over three billion base pairs. How does all this fit into the nucleus of one cell?

38. Take-home message  DNA is shaped like a ladder in which the long vertical sides of the ladder are made from a sequence of sugar-phosphate- sugar-phosphate molecules and the rungs are pairs of nucleotide bases.  The sequence of nucleotide bases contains the information about how to produce a particular protein.

39. Q What is the most common reason why DNA analyses overturn incorrect criminal convictions? DNA As An Individual Identifier

40. Selfish dictators may owe their behaviour partly to their genes, according to a study that claims to have found a genetic link to ruthlessness. –Nature, April 2008

41. DNA in the News

43. RNA is a universal translator, reading DNA and directing protein production.

44. RNA differs from DNA in three important ways.  The sugar molecule of the sugar- phosphate backbone is a ribose  Single-stranded  Uracil (U) replaces thymine (T)

54. Which statement is FALSE when comparing DNA and RNA? 1.Different sugars are used to form the nucleic acids that make DNA and RNA. 2.DNA is double stranded, whereas RNA is single stranded. 3.Both are composed of the bases A, G, T, and C. 4.Only RNA directs the building of a protein in the cytoplasm.