1. Structure and Function of Macromolecules IB Biology
Organic Chemistry
Structure and Function of Macromolecules
IB Biology

2. Vocabulary Check SIZE prefixes Mono Poly Di Miscellaneous
One
Poly
Many Di
Two
Miscellaneous
Lysis = to break
BIOMOLECULE roots
Sacchar-
Sugar
End in -ose
Peptide
Protein
Enzymes: end in -ase
Lipid
Fat

3. The synthesis and breakdown of polymers

4. Dehydration Synthesis & Hydrolysis
Building bigger molecules
Dehydration synthesis
Removing water to create a bigger molecule
Breaking up big molecules
Hydrolysis
Uses water to break apart a big molecule into subunits

5. Building and Breaking Molecules Dehydration Synthesis vs. HydrolysisOH H
OH OH OH
H H H
2H2O
Hydrolysis
2H2O
Dehydration
Synthesis
OH OH OH
H H H OH H
Explanation: A starch molecule (polymer)
becomes the glucose (monomers)
that make it up.
Explanation: 3 Glucose molecules (monomers)
bind to create a Starch molecule (polymer).

6. What does this look like in sugars?
Dehydration Synthesis Reaction
Carbons are numbered (for ease)
Links can be made between different carbons
Glycosidic linkage is a covalent bond between 2 monosaccharides

7. Carbohydrates Energy Source Carbon Source
Cell processes require energy
Mono/disaccharides
Polysaccharides – stored energy (starch for plants, glycogen for animals)
Carbon Source
Structure; building material (cellulose for plants)
Can be used to construct amino acids and fatty acids

8. Monosaccharide Characteristics
Ring structure
Formula = C6H12O6
Generally sweet
Examples: glucose, fructose, galactose, ribose, deoxyribose
Function = Source of quick energy or raw material for creating other molecules

9. Disaccharide Characteristics
2 ring structure with a glycosidic linkage
Formula = C12H22O11
Generally semi-sweet
Examples: sucrose, maltose, lactose
Function = Source of fairly quick energy or raw material for creating other molecules

10. Polysaccharides: Starch vs. Cellulose
Both are chains of glucose
Cellulose does not dissolve in water (cotton does not dissolve when you wash it)
You use starch as an energy source via respiration
You do not have the enzyme to digest cellulose

11. What are Lipids? Hydrophobic molecules (have a “fear” of water)
Most diverse biomolecule category. Examples:
Fats
Phospholipids
Steroids
Waxes & Pigments

12. Lipids Fats (triglycerols) Energy storage in animals.
Fat cells are designed for continuous synthesis and breakdown of triglycerols, controlled mainly by the activation of hormone-sensitive enzyme lipase.
Provides high caloric content, about 9 kcal/g, compared with 4 kcal/g for the breakdown of carbohydrates and proteins.
Migratory birds that must fly long distances without eating use stored energy of triglycerols to fuel their flights.

13. Saturated vs. Unsaturated
As many hydrogen as possible are bonded to the carbon chain.
Solid at room temp.
Unsaturated
One or more double bonds forms a kink.
Liquid at room temp.

14. Saturated vs. Unsaturated Fats
All single bonds
Straight shape, compact
Solid at room temp.
Ex. Butter, lard
UNSATURATED
Include 1+ double bond
Kinked shape, not compact
Liquid at room temp.
Ex. Vegetable oil

15. Phospholipids (cell membranes)
Carbon chain is non-polar (doesn’t dissolve in water)
Phosphate is polar (dissolves in water)

16. Phospholipids Major part of cell membranes Structure:
2 Hydrophobic tails
Hydrophilic head
In a bilayer

17. Steroids
Carbon rings are non-polar
Non-polar means hydrophobic

18. Steroids Regulate organism functioning
Structure: 4 fused rings with different side groups
Note: change in side groups = change in function

19. What’s Up with Proteins?
Amino Acid/peptide = the monomer of proteins
Amino acids join by peptide bonds into a polypeptide
A protein is more than just a chain of polypeptides
Shape is essential!!
COMPONENTS:
Amine group (NH2)
Carboxyl group (COOH)
R group (different for each of 20 amino acids)

20. Protein (amino acid + amino acid + amino acid, etc.)

21. Are proteins diverse? A 20 letter “alphabet”
Proteins can be 100s or 1000s of “letters” long
Imagine the diversity!

22. Protein Functions Structure – support (connective tissue, webs)
Storage – store amino acids; egg white, milk, seeds
Transport – hemoglobin (carries oxygen), channels (H+ through ATP synthase)
Hormonal – regulation; insulin
Receptor – Na+ and K+ receptors in nervous system
Contractile – movement (actin/myosin in muscle)
Defense – antibodies fight bacteria/viruses
Enzymes – speed up chemical reactions

23. 4 levels of Protein Structure
Primary
Unique sequence of amino acids
Secondary
Hydrogen bonds create coils and folds
Alpha helix
Beta pleated sheets
Tertiary
Irregular contortions do to side chain (disulfide bridges)
Quaternary
Two or more polypeptides joined together

24. Levels of Protein Structure
Primary (1°)—amino acid sequence
Secondary (2°)—folds/coils of amino acid change caused by hydrogen bonds
Tertiary (3°)—interactions between R groups
Quaternary (4°)—2+ polypeptides that form one functional protein

25. Primary Structure

26. Secondary Structure

27. Tertiary Structure

28. Quaternary Structure

29. What are Nucleic Acids? Information Storage Molecules
Consist of other molecules
Deoxyribose or Ribose sugars
Phosphate groups (also in some lipids)
Nitrogenous bases
Store the blueprints that make the proteins that create your traits!