1. Biology 12 Unit A The Chemistry of Life – Part 2

2. Macromolecules
Made of organic molecules

3. Organic Molecules Always contain: Carbon (C) and Hydrogen (H)
A carbon atom may share electrons with another carbon atom

4. Organic Molecules Always contain: Carbon (C) and Hydrogen (H)
A carbon atom may share electrons with another carbon atom

5. Organic Molecules Many molecules of life are macromolecules.
(macromolecules contain many molecules joined together)

6. Organic Molecules Many molecules of life are macromolecules.
(macromolecules contain many molecules joined together)
Monomers: Simple organic molecules that exist individually
Polymers: Large organic molecules form by combining monomers

7. Organic Molecules

8. Organic Molecules
A meal containing carbohydrates, lipids, and proteins.

9. Organic Molecules
Cells have mechanisms of joining monomers to build polymers

10. Organic Molecules
Cells have mechanisms of joining monomers to build polymers

11. Organic Molecules
Cells have mechanisms of joining monomers to build polymers
Dehydration Reaction: an -OH and -H are removed
Hydrolysis Reaction: the components of water are added

12. Organic Molecules

13. Macromolecules = BIG molecules
Carbohydrates CH2O
Lipids CHO
-don’t form true polymers, the number of unit molecules that join together is limited
Proteins CHON
Nucleic Acids CHONPS

14. Carbohydrates Some Functions: Quick fuel Short-term energy storage
Structure of organisms
Cell to cell recognition

15. Carbohydrates
Simple Carbohydrates

16. Carbohydrates Simple Carbohydrates
Monosaccharides are sugars with carbon atoms

17. Carbohydrates Simple Carbohydrates
Monosaccharides are sugars with carbon atoms
Pentose refers to a 5-carbon sugar
Hexose refers to a 6-carbon sugar

18. Carbohydrates
Three ways to represent the structure of glucose.

19. Carbohydrates
Disaccharides contain two monosaccharides.

20. Carbohydrates
Polysaccharides are long polymers that contain many glucose subunits.

21. Carbohydrates
Polysaccharides are long polymers that contain many glucose subunits.
Starch is the storage form of glucose in plants.

22. Carbohydrates
Polysaccharides are long polymers that contain many glucose subunits.
Starch is the storage form of glucose in plants.
Glycogen is the storage form of glucose in animals.

23. Carbohydrates
Polysaccharides are long polymers that contain many glucose subunits.
Starch is the storage form of glucose in plants.
Glycogen is the storage form of glucose in animals.
Cellulose can be found in the cell walls of plants.

24. Carbohydrates: starch

25. Carbohydrates: cellulose

26. Carbohydrates: glycogen

27. A3 concept check-up questions
What is the difference between dehydration synthesis and hydrolysis?
Why do lipids not form true polymers?
Water is a by-product of condensation reactions. Where does it come from?
How does the use of glucose in a plant differ from its function in an animal?

28. Lipids

29. Lipids Some Functions: Energy Storage Found in the plasma membrane
Component of steroid hormones
Lipids do not dissolve in water

30. Lipids Some Functions: Energy Storage Found in the plasma membrane
Component of steroid hormones
Lipids do not dissolve in water
Lipids are electrically neutral

31. Lipids
Fats and Oils

32. Lipids Fats and Oils Fats Usually of animal origin
Solid at room temperature

33. Lipids Fats and Oils Fats Usually of animal origin
Solid at room temperature

34. Lipids Fats and Oils Oils Fats Usually of plant origin
Usually of animal origin
Solid at room temperature
Oils
Usually of plant origin
Liquid at room temperature

35. Lipids
Functions of Fats

36. Lipids Functions of Fats Long-term energy storage
Insulation against heat loss
Protection of major organs

37. Lipids
Synthesis and degradation of a fat molecule

38. Lipids
Emulsification

39. Lipids
Saturated and Unsaturated Fatty Acids

40. Lipids Saturated and Unsaturated Fatty Acids
Fatty acids are hydrocarbon chains that end with -COOH.

41. Lipids Saturated and Unsaturated Fatty Acids
Fatty acids are hydrocarbon chains that end
with -COOH.
Saturated fatty acids: No double covalent bonds between carbon atoms
Unsaturated fatty acids: Double bonds between carbon atoms

42. Lipids
Saturated Fatty Acid
Unsaturated Fatty Acid

43. Lipids
Phospholipids

44. Lipids Phospholipids Comprised of 2 fatty acids + a phosphate group
Primary components of cellular membranes

45. Lipids

46. Lipids
Steroids

47. Lipids
Steroids
All steroids have four adjacent rings.

48. Lipids Steroids All steroids have four adjacent rings. Examples:
Cholesterol
Testosterone
Estrogen

49. Lipids

50. A4 concept check up questions
What is the defining characteristic of lipids?
What differences exist between fatty acids from animal sources and fatty acids from plant tissues?
List the ways glycerides can be different from each other.
Name two types of lipids that do not contain glycerol.

51. Proteins Proteins have important functions in cells.
Proteins such as keratin and collagen have structural roles.
Proteins are also enzymes that speed up the chemical reactions of metabolism.
Proteins such as hemoglobin are responsible for the transport of substances within the body.
Proteins also transport substances across cell membranes.

52. Proteins Proteins have important functions in cells.
Proteins form the antibodies of the immune system that defend the body from disease.
Proteins such as insulin are hormones that regulate cellular function.
Contractile proteins such as actin and myosin allow parts of cells to move and muscles to contract.

53. Proteins
Proteins are comprised of amino acids.

54. Proteins Amino acids Amino group (-NH2) Acidic group (-COOH)
R group (remainder)

55. Proteins

56. Proteins Peptides A polypeptide is a single chain of amino acids.
A peptide bond joins two amino acids.

57. Proteins

58. Proteins Levels of Protein Organization
The structure of a protein has three or four levels of organization.
The final shape of a protein is very important
to its function.

59. Proteins

60. Proteins

61. Proteins

62. A5 concept check-up questions
Describe the common structure of amino acids.
What type of bond is a peptide bond? Where can one be found?
What are two types of secondary structure in proteins? What causes the formation of each?
What types of bonds and what level of structure is destroyed when a protein is denatured?

63. Nucleic Acids
DNA (deoxyribonucleic acid)

64. Nucleic Acids
DNA (deoxyribonucleic acid)
RNA (ribonucleic acid)

65. Nucleic Acids DNA stores genetic information in double helix.
DNA codes for the order of amino acids in a protein.
RNA is an intermediary in the sequencing of amino acids into a protein.

66. Nucleic Acids Components of a nucleotide Phosphate
Pentose sugar (ribose or deoxyribose)
Nitrogen-containing base may be 2-ring purine (A, G) or 1-ring pyrimidine (C, T, U)

67. Nucleic Acids
DNA Structure

68. Nucleic Acids

69. Nucleic Acids
ATP (Adenosine Triphosphate)

70. Nucleic Acids ATP (Adenosine Triphosphate) A high energy molecule
ATP undergoes hydrolysis (enzyme ATPase) and energy is released
ATP can be converted to ADP and “recharged” by phosphorylation when 3rd P group is added back on

71. Nucleic Acids

72. A6 concept check-up questions
How do the components of a DNA nucleotide differ from those in an RNA nucleotide?
What’s the difference between a purine and a pyrimidine?
What two types of biochemicals make up chromosomes?
Describe the bonds between the phosphates in ATP. What is their function?