1. Part 2: Organic Chemistry (Carbon and Macromolecules)
BIOCHEMISTRY
Part 2:
Organic Chemistry
(Carbon and Macromolecules)

2. Organic Chemistry Compounds of carbon (and hydrogen and oxygen).
Range from simple to complex molecules
The original idea that organic compounds arise only in organisms, was disproved when chemists began synthesizing them in lab.
The most famous of these was the MILLER-UREY EXPERIMENT.

3. Miller-Urey Experiment

4. Carbon CARBON ATOM: Forms four covalent bonds.
Can form long chains, cyclic or
branched compounds.
Shape is important in determining
biological properties and functions.
HYDROCARBONS consist of only carbon and hydrogen and can release a lot of energy.

5. Polymers
Joining smaller units (monomers) into longer chained molecules called MACROMOLECULES.
DEHYDRATION SYNTHESIS- Linking monomers into large polymers by removing water.
HYDROLYSIS - Breaking polymers into monomers by the addition of water.

6. Carbohydrates Sugars and sugar polymers.
Serve as: fuel for cells and raw material for building molecules.
General formula: (CH2O)n (2 to 1 ratio of H to O).

7. Monosaccharides Simple sugars. Most common: 5 Carbon (Pentose sugars):
Glucose (C6H12O6)- product of photosynthesis used as energy source in cell respiration
Fructose
Galactose
5 Carbon (Pentose sugars):
Ribose (used in RNA)
Deoxyribose (used in DNA)

8. GLUCOSE
FRUCTOSE
GALACTOSE

9. Disaccharides Two monosaccharides joined by dehydration synthesis.
Bond formed is called a GLYCOSIDIC LINKAGE.
Most common:
Maltose (glucose + glucose)
Sucrose (glucose + fructose)
Lactose (glucose + galactose)

10. A – GLUCOSE
B – DEHYDRATION
SYNTHESIS
D – MALTOSE
E – GLYCOSIDIC
LINKAGE
C – HYDROLYSIS

11. Polysaccharides Macromolecules with storage and structural roles.
Examples:
STARCH- Storage polysaccharide in plants, consists entirely of glucose monomers
GLYCOGEN- Storage polysaccharide in animals (humans store this mainly in liver and muscle cells)
CELLULOSE- Major component of tough plant cell walls
CHITIN- Found in the exoskeleton of arthropods and cell walls of fungi

12. Lipids These DO NOT form polymers
HYDROPHOBIC- “water fearing” due to the fact they are non-polar
C, H and (very little) O.
Biologically Important Types:
Neutral Fats
Phospholipids
Steroids
Waxes

13. Neutral Fats Most abundant type. AKA TRIGLYCERIDES.
Stored in fatty tissue in the body.
2 Major Parts:
3 Fatty Acids- carboxyl group attached to a chain of carbons
1 Glycerol
SATURATED FATS – All single bonds between carbons (or maximum hydrogens on carbons).
Mostly solid fats at room temperature.
UNSATURATED FATS – Double/triple bonds between carbons.
Mostly oils at room temperature.
Monounsaturated (one double or triple bond) vs. Polyunsaturated (more than one double or triple bond).

14. Carbon Chain of Fatty Acid Unsaturated Fatty Acid
Carboxyl
Group
Carbon Chain of Fatty Acid
Saturated Fatty Acid
Unsaturated Fatty Acid
Glycerol

15. Dehydration Synthesis
Glycerol
Fatty Acid 1
Fatty Acid 2 3
Fatty Acids
Fatty Acid 3
Dehydration Synthesis
Lipid

18. Fats in Our Diets
HYDROGENATION- process of converting unsaturated fats to saturated fats by adding hydrogen
Hydrogenating vegetable oils also creates “trans fats”.
These appear to contribute to heart disease and should be avoided as much as possible.

19. Phospholipids
Consists of 2 fatty acids and one phosphate group attached to glycerol.
These are AMPHIPATHIC LIPIDS, meaning that one end (fatty acid tails) are hydrophobic and one end (phosphate) is hydrophilic.
This is important because these form the lipid bilayer of the cell membrane and are very stable.

20. Phospholipid Structure

21. Steroids Characterized by 4 interlocking rings.
Important example is CHOLESTEROL, which is a component of animal membranes.
Necessary for proper membrane functioning, but high levels in the blood contribute to cardiovascular disease.

22. General
Steroid
Structure
Progesterone
Estrogen
Testosterone
Aldosterone
Cortisol
Corticosterone
Cholesterol

23. Proteins Account for well over 50% of the dry mass of most cells!
Functions include:
Structure, Storage, Transport, Cell communication, Movement, Enzymes, and Immunity
ENZYMES act as a catalyst to speed up the rate of chemical reactions and work repeatedly.
Building blocks are AMINO ACIDS. They differ in their side chains (R groups) that make up the 20 different amino acids.
Amino acids are linked together by PEPTIDE BONDS.
Long chains of linked amino acids are called POLYPEPTIDES.

24. Side Group
Amino Group
Carboxylic Acid Group
Amino Acid

25. Dehydration Synthesis
Amino Acid (Peptide)
Dehydration Synthesis
Dipeptide
Peptide Bond

27. Protein Structure 4 Major Types:
PRIMARY STRUCTURE – Straight chain of amino acids
SECONDARY STRUCTURE – Folding of short lengths of an amino acid chain with weak hydrogen bonds interaction.
α-helix is coiled and elastic (keratin)
β-pleated sheets are flexible
TERTIARY STRUCTURE - Overall folding of secondary structure due to multiple bonds among various side chains “R” groups.
QUATERNARY STRUCTURE - Two or more polypeptide chains together (e.x. Hemoglobin has 4 polypeptide chains and a heme (Iron) group).

29. A protein’s structure determines its function!
Loss of shape is called DENATURATION (by heat or pH).

31. Nucleic Acids 2 Major Types: Building blocks are NUCLEOTIDES.
Ribonucleic acid (RNA) and Deoxyribonucleic acid (DNA).
Building blocks are NUCLEOTIDES.
3 Parts of a Nucleotide:
Five carbon sugar (ribose or deoxyribose).
Phosphate group.
Nitrogenous base.

32. Bases Double ring bases (PURINES). ADENINE and GUANINE
Single ring bases (PYRIMIDINES).
CYTOSINE and THYMINE (DNA only) and URACIL (RNA only).
Purines always pair up with Pyrimidines.
G-C, A-T (in DNA), A-U (in RNA).

33. Sugar (Deoxyribose)
Phosphate
Base – Adenine
Base – Guanine
Purines
Base – Cytosine
Base – Thymine
Pyrimidines

34. Dehydration Synthesis
Phosphate
Sugar
Base
Dehydration Synthesis
Nucleotide

35. Adenine
Thymine
Phosphate
Sugar
Hydrogen Bonds
Guanine
Cytosine

37. DNA vs. RNA
DNA
RNA
Carrier of genetic code in genes (unit of heredity)
Translation of genetic code
into amino acid sequence
Double helical strand
Single helical strand
Thymine base present
Uracil replaces thymine base
1 Type
3 Types – rRNA, mRNA,
and tRNA

38. ATP ATP (Adenosine TriPhosphate).
Adenine, ribose sugar, and 3 phosphate groups.
2 outer phosphate groups joined by energy rich bonds.
Energy is released when the bonds are broken