1. Biochemistry What is organic?
Usually carbon covalently bonded to carbon
Carbon-containing compounds in living things
EXCLUDES carbon dioxide, carbonates, etc.
What are the common elements in organic chemistry? How many bonds do they make?
H = 1
O = 2
N = 3
C = 4
P = 5

2. Macromolecules Large molecules composed of smaller molecules
Most are Polymers made of monomers
Three of the classes of organic molecules are polymers
Carbohydrates
Proteins
Nucleic acids
Not all form polymers
Lipids some polymerize, some don’t

3. Building up Macromolecules CONDENSATION Reactions (water comes out) monomers  polymers
Monomers form larger molecules called polymers by condensation reactions HO H 1 2 3 4
H2O
Short polymer
Unlinked monomer
Longer polymer
Dehydration removes a water molecule, forming a new bond
Sometimes
Called
Dehydration
Synthesis

4. Condensation Reactions
Join monomers together (creates a covalent bond)
Creates a water molecule (hydroxyl (OH) from one monomer and hydrogen (H) from the other)

5. Breaking down Macromolecules HYDROLYSIS (means “water” to “split”) polymers  monomers
Polymers disassemble HO 1 2 3 H 4
H2O
Hydrolysis adds a water molecule, breaking a bond

6. Hydrolysis Reactions Condensation reactions in reverse
Water is used up
Produces monomers from polymers

7. Categories of Macromolecules
Carbohydrates
Lipids
Proteins

8. I. Carbohydrates (Carbs)
Made up of monosaccharides
Polymerize to form disaccharides and polysaccharides (complex carbs)
All contain carbon, oxygen, and hydrogen
Usually have the formula: [C(H2O)]n
Often have a ring structure:

9. Simple Carbs: Monosaccharides
Simple sugars
Sweet taste
Functions
fuel (quick energy)
Building materials: Can be combined into polymers
Examples include:
Fructose – gives sweet taste to many fruits
Glucose – part of metabolism, found in blood and sap
Ribose (and deoxyribose) – in RNA (and DNA)
Galactose – in peas, and PART of lactose

10. Carbs: Examples of monosaccharides
Glucose Fructose Galactose
Glucose Ribose Deoxyribose
Find the differences and similarities

11. Carbs: Disaccharides Two monosaccharides covalently bonded: + ==
Examples include:
sucrose (table sugar)
lactose (in milk)
maltose (“malt” flavoring)

12. Complex Carbs: Polysaccharides
Many sugars covalently bonded together
Examples include:
Chitin: used for strength and support in insect skeletons and fungal cell walls (glucosamine)
Cellulose: used for strength and support in plant cell walls (β-glucose)
Glycogen: used for energy storage in animals found in human heart and muscles (α-glucose)
Starch: used for energy storage in plants (a-glucose)

13. Carbs: Polysaccharide examples
Chitin =
Cellulose =
Glycogen =
Starch =

14. Carbohydrate summary Carbohydrate: 3 examples: Use in animals:
Use in plants:
Monosaccharides
Glucose
Fructose
Galactose
Carried in blood to supply energy to the body
Sweetens fruits to help seed dispersal (attracts animals)
Disaccharides
Lactose
Sucrose
Maltose
In milk to provide energy to dependent young
Carried by (some) phloem (sap) to supply energy
Polysaccharides
Glycogen
Cellulose
Starch
In liver and muscles for short-term energy storage
Forms strong fibers in cell wall

15. II. Lipids Lipids are mostly non-polar molecules.
Used in energy storage, membrane structure, insulation, cell-to-cell communication, buoyancy, and more.
Two building blocks: /OH
Glycerol:C3H8O Fatty acid:CH3-(CH2)x-C=O

16. Building Lipids Condensation to form Triglycerides
Glyerol bonded to a fatty acid makes a triyeride
Monoglyceride = glycerol + 1 fatty acid
Diglyceride = glycerol + 2 fatty acids
Triglyceride = glycerol + 3 fatty acids

17. Fatty acids can be saturated, unsaturated and polyunsaturated
No double bonds
Straight chains of carbon
Stack easily
Usually solid
at room temperature
Cis double bonds
Don’t stack as well
(think of Tetris)
Usually liquid at
room temperature
Trans double bonds
Mimics saturated
Can solidify at room temp
Clogs arteries
Worse for health
Polyunsaturated? Many d.b.’s very kinky (liquid) better for health

18. Comparing Lipids vs. Carbohydrates
~9 Calories / gram
Long-term storage
Non-polar (water insoluble)
~4 Calories / gram
Short-term storage
Polar, water soluble

19. The Love / Hate Relationship with Carbs and Lipids

20. III. Proteins Made of amino acids linked by peptide bonds
There are 20 types of amino acids that we use (though many more exist)

21. The Amino Acids
Compare each:
What’s the same?
What’s different?

22. Protein Structure Final Overall 3-D Shape ~
Primary - order of amino acids
Secondary - H-bonds in backbone
Tertiary - 3D shape from R-groups
Quaternary - 2+ polypeptides and prosthetic groups
Final Overall 3-D Shape ~
Critical point: Form fits Function!

23. Significance of amino acid variety
The different R-groups allow a variety of shapes
The active sites of enzymes have the correct polarity and/or charge to attract the substrates
Non-polar amino acids can be anchored in non-polar membranes
A membrane channel protein can have non-polar r-groups on the outside and polar r-groups on the inside, creating a hydrophilic passageway through the membrane

24. Proteins: Building (Condensation) and Breaking (Hydrolysis)
Condensation (dehydration): joins amino acids into a dipeptide or polypeptide, produces water
Hydrolysis: breaks a polypeptide into amino acids, uses water