1. Chapter 2: The Structure and Function of Macromolecules

2. Polymer Principles
POLYMER: large molecule consisting of many identical or similar subunits connected together
MONOMER: subunit or building block molecule of a polymer
MACROMOLECULE: large organic polymer
*Examples: carbohydrates, lipids, proteins, nucleic acids

3. OH HO
Glucose C6H12O6
Fructose C6H12O6
H2O O
Sucrose C12H22O11
Water

4. H2O O
Sucrose C12H22O11
Water OH HO
Glucose C6H12O6
Fructose C6H12O6

6. Carbohydrates

7. Monosaccharides = single sugars
are major nutrients for cells
glucose is most common
*examples: glucose, ribose, galactose, fructose
~OSE

8. Disaccharides = double sugars
Also a source of energy
Formed when 2 monosaccharides combine in a dehydration reaction;
Examples:
 lactose (milk sugar): glucose + galactose
 sucrose (table sugar): glucose + fructose

9. Polysaccharides = hundreds or thousands of monosaccharides

10. Disaccharide

11. Examples of energy storage polysaccharides:
starch = glucose polymer in plants used for energy storage (in roots, tubers, etc.)
glycogen = glucose polymer in animals stored in skeletal muscles and liver of humans & other vertebrates

13. Examples of structural support polysaccharides:
cellulose = structural component of plant cell walls that cannot be digested by most organisms
chitin = forms exoskeletons of arthropods

15. Lipids!!

16. LIPIDS insoluble in water (because they are NONPOLAR, or HYDROPHOBIC)
 include:
Fats
Phospholipids
Steroids

17. 1. FATS
Composed of:
 A large proportion of C-H bonds and less oxygen than carbohydrates
(the nonpolar C-H bonds make the chain hydrophobic and insoluble in water)
 Example: C57H110O6

18. Fatty acids may vary in # of carbon atoms (usually even #)

19. Saturated vs. Unsaturated Fats
 no C-C double bonds in fatty acid tail
 usually solid at room temp.
 most animal fats
 e.g., bacon grease, lard, butter
 one or more C-C double bonds in fatty acid tail
 usually a liquid at room temp.
 most plant fats
 e.g., corn, peanut, olive oils

21. Functions of Fats
energy storage (1 g of fat stores 2x as much energy as 1 g of carbohydrate)
cushions vital organs in mammals (e.g. kidney)
insulates against heat loss (e.g. whales, seals)

22. 2. PHOSPHOLIPIDS
Important component of cell membranes

23. 3. STEROIDS
Important component of some hormones

24. Cholesterol …
is used to make many other steroids (including sex hormones in vertebrates)
common
component
of cell membranes
can cause atherosclerosis (if have too much)