1. Chapter 4~ Carbon & The Molecular Diversity of Life
Chapter 5~ The Structure & Function of Macromolecules

2. Organic chemistry Biological thought:
Vitalism (life force outside physical & chemical laws) – organic compounds can only arise in living organisms - Berzelius
Mechanism (all natural phenomena are governed by physical & chemical laws) – organic compounds may be produced in lab - Miller
Carbon
Ability to branch in 4 directions allows large molecules possible
Tetravalence, tetrahedron
Shape determines function

3. Hydrocarbons Only carbon & hydrogen (petroleum; lipid ‘tails’)
Covalent bonding; nonpolar
High energy storage
Isomers (same molecular formula, but different structure & properties)
1. Structural~differing covalent bonding arrangement
2. Geometric~differing spatial arrangement
3. Enantiomers~mirror images pharmacological industry (thalidomide)

4. Functional Groups, I
Attachments that replace one or more of the hydrogens bonded to the carbon skeleton of the hydrocarbon
Each has a unique property from one organic to another
1. Hydroxyl Group
H bonded to O (-OH);
alcohols; polar (oxygen); solubility in water
2. Carbonyl Group
C double bond to O
At end of C skeleton - aldehyde - ex. proponal
Within C skeleton – ketone – ex. acetone

5. Functional Groups, II 5. Sulfhydral Group 6. Phosphate Group
3. Carboxyl Group
O double bonded to C to hydroxyl
carboxylic acids, organic acids
covalent bond between O and H is very polar leads to dissociation,
H ion
4. Amino Group
N to 2 H atoms (-NH2)
Amines
acts as a base
5. Sulfhydral Group
sulfur bonded to H
thiols
6. Phosphate Group
phosphate ion covalently attached by 1 of its O to the C skeleton
transfer energy

6. Polymers Macromolecules – may have thousands of linked molecules
Poly = many; mers = parts
Covalent monomers link to form polymers
Condensation reaction (dehydration reaction):
One monomer provides a hydroxyl group while the other provides a hydrogen to form a water molecule
Forms polymers
Hydrolysis: bonds between monomers are broken by adding water (digestion) – aided by enzymes

7. Carbohydrates, I Monosaccharides CH2O (1:2:1) formula
Multiple hydroxyl (-OH) groups and 1 carbonyl (C=O) group
Location determines if aldehyde (aldose) sugar or ketone (ketose) sugar
Cellular respiration breaks them down
Raw material for amino acids and fatty acids
Ex. Glucose, fructose

8. Carbohydrates, II Disaccharides
Glycosidic linkage (covalent bond) between 2 monosaccharides
No longer have 1:2:1 multiples – water is pulled out (condensation/ dehydration reaction)
Sucrose (table sugar) -most common disaccharide

9. Carbohydrates, III Polysaccharides
Storage: Starch~ glucose monomers Plants: plastids Animals: glycogen
Polysaccharides Structural: Cellulose~ most abundant organic compound; Chitin~ exoskeletons; cell walls of fungi; surgical thread

10. Lipids, I Fats, phospholipids, steroids
No polymers; glycerol and fatty acid
Glycerol – alcohol w/ 3C each w/ hydroxyl group
Fatty acid – long C chain w/ carboxyl group
Non-polar C-H bonds in fatty acid ‘tails’
Cause to be hydrophobic
Ester linkage: 3 fatty acids to 1 glycerol (dehydration formation)
Triacyglycerol (triglyceride)
Saturated (solid) vs. unsaturated (liquid) fats; single vs. double bonds

11. Lipids, II Phospholipids
2 fatty acids instead of – replaced by a phosphate group
‘Tails’ hydrophobic; ‘heads’ hydrophilic
Micelle (phospholipid droplet in water)
Form a bilayer (double layer) - cell membranes

12. Lipids, III Steroids Lipids with 4 fused carbon rings Ex: cholesterol:
Cell membranes
Precursor for other steroids (sex hormones – estrogen, testosterone)
Too mcuh = atherosclerosis – narrowing of vessel walls

13. Proteins, I
Importance - instrumental in nearly everything organisms do; 50% dry weight of cells; most structurally sophisticated molecules known – enzymes, insulin, antibodies
Monomer: amino acids (there are 20)
Contain a carboxyl (-COOH) group, amino group (NH2), H atom, variable group (R – aka side chain – gives each its identity and properties)
Variable group characteristics: polar (hydrophilic), nonpolar (hydrophobic), acid or base
Three-dimensional shape – conformation – determines function
Polypeptides (dehydration reaction)
Joined by peptide bonds (covalent bond); carboxyl group to amino group (polar)

14. Proteins, II Primary Structure Conformation: Linear structure
Molecular Biology: each type of protein has a unique primary structure of amino acids
Ex: lysozyme
Amino acid substitution: hemoglobin; sickle-cell anemia

15. Proteins, III Secondary Structure
Conformation: coils & folds (hydrogen bonds)
Alpha Helix: coiling; keratin
Beta Pleated Sheet: parallel; silk

16. Proteins, IV Tertiary Structure
Conformation: irregular contortions from R group bonding
hydrophobic
disulfide bridges
hydrogen bond
ionic bonds

17. Proteins, V Quaternary Structure
Conformation: 2 or more polypeptide chains aggregated into 1 macromolecule
collagen (connective tissue)
hemoglobin
Heat, pH, other body disturbances may denature protein (becomes inactive) – loses conformation

18. Nucleic Acids, I Deoxyribonucleic acid (DNA) Ribonucleic acid (RNA)
DNA>RNA>protein
Polymers of nucleotides (polynucleotide):
nitrogenous base
pentose – 5 carbon sugar
phosphate group
Nitrogenous bases:
Pyrimidines – single ring ~cytosine, thymine (DNA), uracil (RNA)
Purines – double ring~adenine, guanine

19. Nucleic Acids, II Pentoses: Polynucleotide: ribose (RNA)
deoxyribose (DNA)
nucleoside (base + sugar)
Polynucleotide:
phosphodiester linkages (covalent) – btw phosphate + sugar

20. Nucleic Acids, III Inheritance based on DNA replication
Double helix (Watson & Crick )
H bonds~ between paired bases
van der Waals~ between stacked bases
A to T; C to G pairing
Complementary