1. The Structure and Function of Macromolecules
Chapter 5
The Structure and Function of Macromolecules

2. Introductory Terms Macromolecule = “giant” molecule of living matter
Monomer = subunits that serve as the building blocks of a polymer
Example: Lego block
Polymer = monomers linked together
Example: Lego castle

3. Macromolecular Reactions 
Dehydration Synthesis:
2 molecules become covalently bonded to each other through the loss of water
Hydrolysis:
Water is used to break up polymers to monomers

4. Macromolecular Diversity
Diversity in polymers is due to differing arrangements of monomers…
Nearly infinite possibilities…
Alphabet analogy

5. Carbohydrates Structure: Functions: C:H:O in a 1:2:1 Ratio
Example: C6H12O6
Functions:
Short-term energy storage
Pasta dinner before the big race, game, etc.
Structural Support

6. Carbohydrates Monosaccharides: “one sugar” C:H:O Ratio = 1:2:1
Glucose (C6H12O6) is a monosaccharide

7. Carbohydrates Disaccharides: “double sugar”
2 monosaccharides joined together by a glycosidic linkage (covalent bond)
Sucrose = glucose + fructose

8. Carbohydrates Polysaccharides
Polymers in which a few hundred to a few thousand monosaccharides are linked together
Starch and glycogen are examples

9. Carbohydrates Structural Polysaccharides Cellulose Chitin
Major component of plant cell walls
Cannot be digested by humans
Fiber!
Chitin
Used by arthropods to build exoskeletons
Cell wall of fungi

10. Lipids Structure: Functions: Made up of carbon, hydrogen, oxygen
Do not dissolve in water
Functions:
Long-term energy storage
Chemical messengers (hormones)
Insulation
Waxes

11. Lipids Fats Made of glycerol and 3 fatty acids
Fatty acid has a long carbon skeleton and a carboxyl group
C-H bonds responsible for hydrophobia of fats

12. Lipids Fats Saturated Fat = no double bonds
Saturated with hydrogen
Unsaturated Fat = double bonds
Not saturated with hydrogen

13. Lipids Phospholipids Have only 2 fatty acids
Instead of 3rd fatty acid, they have a phosphate group
Major component of cell membrane

14. Lipids Steroids Made up of 4 interconnected rings Examples:
Cholesterol
Testosterone
Estrogen

15. Proteins *** Most of a cell is made up of proteins
Instrumental in almost everything organisms do
Structure:
All proteins are created from unique combinations of 20 different amino acids
C,H,O,N
Major Functions:
Structure
Defense (antibodies)
Enzymes

16. Proteins Amino Acids Amino acids are the monomers of proteins
Organic molecules possessing both carboxyl and amino groups
20 types of AAs that make up 1000s of different proteins
AAs are linked together by peptide bonds

17. Amino Acids

18. Proteins
A protein is one or more polypeptides precisely twisted, folded and coiled into a molecule of unique shape (3-D)
4 Levels of Protein Structure
Primary Structure
Unique sequence of AAs
Example: Tryptophan-leucine-glycine-glycine-lysine-phenylalanine-serine-leucine
Sickle Cell Anemia

19. Proteins Secondary, Tertiary, Quaternary Structure:
The amino acid chain is folded into unique shapes because of hydrogen-bonding
This gives each protein a unique shape

20. Proteins Denaturation:
When pH, salt concentration, temperature, and/or other environmental factors are altered, the protein may unravel and lose its shape
Biologically inactive
Structure + function

21. Nucleic Acids Structure Function DNA and RNA
Made up of long chains of nucleotides
CHNOPS
Function
Carries genetic material from one generation to the next
DNA and RNA