1. The structure and function of large biological molecules

2. Four classes of biological molecules
Carbohydrates
Lipids
Proteins
Nucleic acids

3. Key concepts Macromolecules are polymers built from monomers
Carbohydrates serve as fuel and building material
Lipids are a diverse group of hydrophobic molecules
Proteins have many structures, resulting a wide range of functions
Nucleic acids store and transmit hereditary information

4. Macromolecules are polymers, built from monomers

5. Macromolecules are polymers, built from monomers
What is a macromolecule?

6. Macromolecules are polymers, built from monomers
What is a macromolecule?
Large and complex molecules, often chainlike

7. Macromolecules are polymers, built from monomers
What is a macromolecule?
Large and complex molecules, often chainlike
Monomer (simple subunits) building blocks form the chains
Monomer

8. Macromolecules are polymers, built from monomers
What is a macromolecule?
Large and complex molecules, often chainlike
Monomer (simple subunits) building blocks form the chains
Chains are called polymers
Polymer
Monomer

9. Macromolecules are polymers, built from monomers
What is a macromolecule?
Large and complex molecules, often chainlike
Monomer (simple subunits) building blocks form the chains
Chains are called polymers
Monomers are connected via dehydration reactions

10. Macromolecules are polymers, built from monomers
What is a macromolecule?
Large and complex molecules, often chainlike
Monomer (simple subunits) building blocks form the chains
Chains are called polymers
Monomers are connected via dehydration reactions
What’s a dehydration reaction?

11. Macromolecules are polymers, built from monomersHO 1 2 3 H HO H
Short polymer
Unlinked monomer
Dehydration removes a water
molecule, forming a new bond
H2O HO 1 2 3 4 H
Longer polymer

12. Macromolecules are polymers, built from monomersHO 1 2 3 H HO H
Short polymer
Unlinked monomer
Dehydration removes a water
molecule, forming a new bond
This process can also be reversed
H2O HO 1 2 3 4 H
Longer polymer

13. Macromolecules are polymers, built from monomers
Hydrolysis 1 2 3 H HO HO 1 2 3 4 H
Hydrolysis adds a water
molecule, breaking a bond
H2O
H2O 1 2 3 4 HO 1 2 3 H HO H

14. Macromolecules are polymers, built from monomers
Which of these is NOT a polymer?
Carbohydrates
Lipids
Proteins
Nucleic acids 1 2 3
H2O 1 2 3 4

15. Macromolecules are polymers, built from monomers

16. Carbohydrates serve as fuel and building material

17. Carbohydrates serve as fuel and building material
What is a carbohydrate?

18. Carbohydrates serve as fuel and building material
Carbohydrates include:
Sugars
Polymers of sugars

19. Carbohydrates serve as fuel and building material
Carbohydrates include:
Sugars (monosaccharides and disaccharides)

20. Carbohydrates serve as fuel and building material
Carbohydrates include:
Sugars (monosaccharides and disaccharides)
Molecular formula is generally some multiple of CH2O
Glucose is a common monosaccharide (C6H12O6)
Glucose is a source of cellular energy

21. Carbohydrates serve as fuel and building material
Carbohydrates include:
Sugars (monosaccharides and disaccharides)
Two monosaccharides joined by a covalent bond (glycosidic linkage)
Examples are sucrose and maltose
Dehydration reaction in the synthesis of maltose

22. Carbohydrates serve as fuel and building material
Carbohydrates include:
Sugars (monosaccharides and disaccharides)
Two monosaccharides joined by a covalent bond (glycosidic linkage)
Examples are sucrose and maltose
Transport sugars in plants

23. Carbohydrates serve as fuel and building material
Carbohydrates include:
Sugars (monosaccharides and disaccharides)
Two monosaccharides joined by a covalent bond (glycosidic linkage)
Examples are sucrose and maltose
Transport sugars in plants
Often found in energy supplements

24. Carbohydrates serve as fuel and building material
Carbohydrates include:
Sugars (monosaccharides and disaccharides)
Polymers of sugars (polysaccharides)
Polymers of a few hundred to a few thousand monosaccharides joined by glycosidic linkages

25. Carbohydrates serve as fuel and building material
Carbohydrates include:
Sugars (monosaccharides and disaccharides)
Polymers of sugars (polysaccharides)
Polymers of a few hundred to a few thousand monosaccharides joined by glycosidic linkages
Energy storage polysaccharides
Structural polysaccharides

26. Carbohydrates serve as fuel and building material
Carbohydrates include:
Sugars (monosaccharides and disaccharides)
Polymers of sugars (polysaccharides)
Polymers of a few hundred to a few thousand monosaccharides joined by glycosidic linkages
Energy storage polysaccharides
Structural polysaccharides
Different forms in plants and animals

27. Carbohydrates serve as fuel and building material
Energy storage polysaccharides (both polymers of glucose)
(b) Glycogen: an animal polysaccharide
Starch
Glycogen
Amylose
Chloroplast
(a) Starch: a plant polysaccharide
Amylopectin
Mitochondria
Glycogen granules
0.5 µm
1 µm

28. Carbohydrates serve as fuel and building material
Energy storage polysaccharides (both polymers of glucose)
(b) Glycogen: an animal polysaccharide
Starch
Glycogen
Amylose
Chloroplast
(a) Starch: a plant polysaccharide
Amylopectin
Mitochondria
Glycogen granules
0.5 µm
1 µm
How does an organism get energy from these molecules?

29. Carbohydrates serve as fuel and building material
Carbohydrates include:
Sugars (monosaccharides and disaccharides)
Polymers of sugars (polysaccharides)
Polymers of a few hundred to a few thousand monosaccharides joined by glycosidic linkages
Energy storage polysaccharides
Structural polysaccharides

30. Carbohydrates serve as fuel and building material
Carbohydrates include:
Sugars (monosaccharides and disaccharides)
Polymers of sugars (polysaccharides)
Polymers of a few hundred to a few thousand monosaccharides joined by glycosidic linkages
Energy storage polysaccharides
Structural polysaccharides
i.e. cellulose

31. Carbohydrates serve as fuel and building material
Structural polysaccharides
Cellulose
The most abundant organic molecule on Earth
Major component of plant cell walls
Made of glucose monomers (Beta linkages)

32. Carbohydrates serve as fuel and building material
Structural polysaccharides
i.e. Cellulose
The most abundant organic molecule on Earth
Major component of plant cell walls
Made of glucose monomers (Beta linkages)
Unbranching
Forms microfibrils
Very strong building
material
Glucose
monomer
Cellulose
molecules
Microfibril
microfibrils
in a plant
cell wall
0.5 µm
10 µm
Cell walls

33. Carbohydrates serve as fuel and building material

34. Lipids are a diverse group of hydrophobic molecules

35. Lipids are a diverse group of hydrophobic molecules
This group includes:
Fats
Phospholipids
Steroids
**All are hydrophobic (they do not mix well with water)

36. Lipids are a diverse group of hydrophobic molecules
Fats
Constructed from glycerol (an alcohol) and fatty acids (long hydrocarbon chains with a carboxyl group)
Form by dehydration reactions
Fatty acid
(palmitic acid)
Glycerol
(a) Dehydration rxn in fat synthesis
Ester linkage
(b) Fat molecule (triacylglycerol)

37. Lipids are a diverse group of hydrophobic molecules
Fats
Constructed from glycerol (an alcohol) and fatty acids (long hydrocarbon chains with a carboxyl group)
Form by dehydration reactions
Can be saturated or unsaturated
Structural
formula of a
saturated fat
molecule
Stearic acid, a
saturated fatty
acid
(a) Saturated fat
Structural formula
of an unsaturated
fat molecule
Oleic acid, an
unsaturated
fatty acid
(b) Unsaturated fat
cis double
bond causes
bending

38. Lipids are a diverse group of hydrophobic molecules
Fats
Constructed from glycerol (an alcohol) and fatty acids (long hydrocarbon chains with a carboxyl group)
Form by dehydration reactions
Can be saturated or unsaturated
Their function is energy storage (they store twice as much energy as starch)
Biodiesel

39. Lipids are a diverse group of hydrophobic molecules
Phospholipids
Major component of cell membranes
Consist of a glycerol with two fatty acids and a phosphate group

40. Lipids are a diverse group of hydrophobic molecules
Phospholipids
Major component of cell membranes
Consist of a glycerol with two fatty acids and a phosphate group
Polar nature of the molecule causes self-assembling of membranes

41. Lipids are a diverse group of hydrophobic molecules
Steroids
Lipids with a carbon skeleton that contains four fused rings

42. Lipids are a diverse group of hydrophobic molecules
Steroids
Lipids with a carbon skeleton that contains four fused rings
Includes hormones-Secreted chemicals that that travel through the body to act on a target

43. Lipids are a diverse group of hydrophobic molecules
Steroids
Lipids with a carbon skeleton that contains four fused rings
Includes hormones-Secreted chemicals that that travel through the body to act on a target
Also includes cholesterol-common component of animal cell membranes and a precursor from which other steroids are synthesized

44. Lipids are a diverse group of hydrophobic molecules

45. Proteins have many structures resulting in a wide range of functions

46. Proteins have many structures resulting in a wide range of functions
Protein structure
Proteins are made from amino acid monomers
All amino acids have a carboxyl group, an amino group, and an R group (variable)

47. Proteins have many structures resulting in a wide range of functions
Nonpolar
Glycine
(Gly or G)
Alanine
(Ala or A)
Valine
(Val or V)
Leucine
(Leu or L)
Isoleucine
(Ile or I)
Methionine
(Met or M)
Phenylalanine
(Phe or F)
Trypotphan
(Trp or W)
Proline
(Pro or P)
Polar
Serine
(Ser or S)
Threonine
(Thr or T)
Cysteine
(Cys or C)
Tyrosine
(Tyr or Y)
Asparagine
(Asn or N)
Glutamine
(Gln or Q)
Electrically
charged
Acidic
Basic
Aspartic acid
(Asp or D)
Glutamic acid
(Glu or E)
Lysine
(Lys or K)
Arginine
(Arg or R)
Histidine
(His or H)
Protein structure
Proteins are made from amino acid monomers
All amino acids have a carboxyl group, an amino group, and an R group (variable)
The R group determines the properties of the amino acid

48. Proteins have many structures resulting in a wide range of functions
Protein structure
Proteins are made from amino acid monomers
All amino acids have a carboxyl group, an amino group, and an R group (variable)
The R group determines the properties of the amino acid
Polypeptide polymers form when the carboxyl end is adjacent to an amino end (dehydration reaction forms a peptide bond)
Peptide
bond
Amino end
(N-terminus)
Side chains
Backbone
Carboxyl end
(C-terminus)
(a)
(b)

49. Proteins have many structures resulting in a wide range of functions
Protein structure
The amino acid sequence represents the proteins primary structure

50. Proteins have many structures resulting in a wide range of functions
Protein structure
The amino acid sequence represents the protein’s primary structure
Secondary structure includes coils (alpha helices) and pleats (beta pleated sheets). Both result from H-bonds between amino and carbonyl group of nearby amino acids.
 pleated sheet
Examples of
amino acid
subunits
 helix

51. Proteins have many structures resulting in a wide range of functions
Protein structure
Tertiary structure results from interactions between R-groups. Interactions include: hydrophobic interactions (leading to hydrophobic cores), hydrogen and ionic bonds, disulfide bridges
Hydrogen
bond
Disulfide bridge
Ionic bond

52. Proteins have many structures resulting in a wide range of functions
Protein structure
Quaternary structure results from aggregation of multiple polypeptide subunits

53. Proteins have many structures resulting in a wide range of functions
Protein function
Proteins serve many important functions. Act as enzymes, cell signaling, movement, immune functions, etc.
Protein structure is often critical to their function (it often depends on the ability to recognize or bind other molecules)
Antibody protein
Protein from flu virus

54. Proteins have many structures resulting in a wide range of functions
Protein function
Proteins serve many important functions. Act as enzymes, cell signaling, movement, immune functions, etc.
Protein structure is often critical to their function (it often depends on the ability to recognize or bind other molecules)
Environmental conditions can lead to protein denaturation (hence protein dysfunction)

55. Proteins have many structures resulting in a wide range of functions
Protein function
Proteins serve many important functions. Act as enzymes, cell signaling, movement, immune functions, etc.
Protein structure is often critical to their function (it often depends on the ability to recognize or bind other molecules)
Environmental conditions can lead to protein denaturation (hence protein dysfunction)

56. Proteins have many structures resulting in a wide range of functions

57. Nucleic acids store and transmit hereditary information

58. Nucleic acids store and transmit hereditary information
The role of nucleic acids
RNA and DNA are nucleic acids
DNA is the genetic material inherited from parents
DNA contains the information that programs all of life’s activities (RNA helps relay the information)
DNA to RNA to proteins

59. Nucleic acids store and transmit hereditary information
The structure of nucleic acids
Nucleotide monomers link to form polynucleotides (or nucleic acids)
5' end
5'C
3'C
Phosphate
group
Nitrogenous
base
5'C
3'C
5'C
Sugar
3'C
3' end

60. Nucleic acids store and transmit hereditary information
The structure of nucleic acids
Nucleotide monomers link to form polynucleotides (or nucleic acids)
Nucleotides contain three parts:
Nitrogenous base
Purines (Adenine and Guanine)
Pyrimidines (Cytosine, Thymine, Uracil)
5-C sugar (Deoxyribose in DNA, Ribose in RNA)
Phosphate group
5' end
5'C
3'C
Phosphate
group
Nitrogenous
base
5'C
3'C
5'C
Sugar
3'C
3' end

61. Nucleic acids store and transmit hereditary information
The structure of nucleic acids
Nucleotide monomers link to form polynucleotides (or nucleic acids)
Nucleotides contain three parts:
Nitrogenous base
Purines (Adenine and Guanine)
Pyrimidines (Cytosine, Thymine, Uracil)
5-C sugar (Deoxyribise in DNA, Ribose in RNA)
Phosphate group
Adjacent nucleotides are joined by a phosphodiester linkage (phosphate group that links the sugars of two nucleotides)
5' end
5'C
3'C
Phosphate
group
Nitrogenous
base
5'C
3'C
5'C
Sugar
3'C
3' end

62. Nucleic acids store and transmit hereditary information
The structure of nucleic acids
Nucleotide monomers link to form polynucleotides (or nucleic acids)
Nucleotides contain three parts:
Nitrogenous base
Purines (Adenine and Guanine)
Pyrimidines (Cytosine, Thymine, Uracil)
5-C sugar (Deoxyribise in DNA, Ribose in RNA)
Phosphate group
Adjacent nucleotides are joined by a phosphodiester linkage (phosphate group that links the sugars of two nucleotides)
5' end
5'C
3'C
Phosphate
group
Nitrogenous
base
Notice the distinct 5’ and 3’ ends
5'C
3'C
5'C
Sugar
3'C
3' end

63. Nucleic acids store and transmit hereditary information
The DNA double helix
Unlike RNA, DNA consists of two polynucleotides that form a double helix
5' end
3' end
5’-AGTACG-3’
3’-TCATGC-5’
3' end
5' end

64. Nucleic acids store and transmit hereditary information
The DNA double helix
Unlike RNA, DNA consists of two polynucleotides that form a double helix
The two polynucleotides run in opposite 5 → 3 directions (antiparallel)
5' end
3' end
5’-AGTACG-3’
3’-TCATGC-5’
3' end
5' end

65. Nucleic acids store and transmit hereditary information
The DNA double helix
Unlike RNA, DNA consists of two polynucleotides that form a double helix
The two polynucelotides run in opposite 5 → 3 directions (antiparallel)
The nitrogenous bases pair up and form hydrogen bonds: adenine (A) always with thymine (T), and guanine (G) always with cytosine (C)
5' end
3' end
5’-AGTACG-3’
3’-TCATGC-5’
3' end
5' end

66. Nucleic acids store and transmit hereditary information
The DNA double helix
Unlike RNA, DNA consists of two polynucleotides that form a double helix
The two polynucelotides run in opposite 5 → 3 directions (antiparallel)
The nitrogenous bases pair up and form hydrogen bonds: adenine (A) always with thymine (T), and guanine (G) always with cytosine (C)
The strands are complimentary!
5' end
3' end
3' end
5' end

67. Nucleic acids store and transmit hereditary information
The DNA double helix
Unlike RNA, DNA consists of two polynucleotides that form a double helix
The two polynucelotides run in opposite 5 → 3 directions (antiparallel)
The nitrogenous bases pair up and form hydrogen bonds: adenine (A) always with thymine (T), and guanine (G) always with cytosine (C)
The strands are complimentary!
5' end
3' end
How would an RNA molecule look different?
3' end
5' end

68. Nucleic acids store and transmit hereditary information

69. Key concepts Macromolecules are polymers built from monomers
Carbohydrates serve as fuel and building material
Lipids are a diverse group of hydrophobic molecules
Proteins have many structures, resulting a wide range of functions
Nucleic acids store and transmit hereditary information