1. Macromolecules

2. The classes of organic molecules
Carbohydrates
Lipids
phospholipids and steroids
Proteins
Nucleic Acids

3. Class Monomer(s) Polymer(s) Carbohydrates monosaccharides
polysaccharides
Proteins
amino acids
polypeptides
fats, phospholipids, steroids
Lipids
fatty acids and glycerol
Nucleic acids
nucleotides
polynucleotides

4. Carbohydrates Monomer: called a monosaccharide
based on a molecule composed of carbon, hydrogen and oxygen.
molecular formulas are multiples of the structural formula CH2O, like C6H12O6.

5. Aldose sugars = aldehyde group
enantiomers
structural isomers
Ketose sugars = ketone group

6. Sugars form rings in aqueous solution
glucose

7. Functions of monosaccharides…
Fuel metabolism (cellular respiration)
Also used as the raw material to build other types of organic molecules (fatty acids, amino acids…)

8. Carbohydrates: polymers
Disaccharides: “two sugars”
SUCROSE =
GLUCOSE + FRUCTOSE
SUCROSE

9. Glucose ring structures
formed in solution
a= OH down
b = OH up

10. Carbohydrates: polymers
Polysaccharides:

11. Why does this matter?
a 1->4 linkages are digestible by humans; starch
b 1->4 linkages are not; cellulose
Every other glucose is “upside down”

12. Functions of polysaccharides…
Carbohydrate energy storage
starch
(in plants)
glycogen
(in animals)

13. Functions of polysaccharides…
Structure
Cellulose of plant cell walls
Chitin of the cell walls of fungi and exoskeleton of insects

15. Lipids Monomers: Fatty acids Glycerol carboxyl
long chains of carbons and hydrogens linked by non-polar covalent bonds with a carboxyl group stuck on one end
Jl;lkjlkj
Glycerol
a small 3 carbon molecule (C3H8O3)

16. Lipids… Polymers: Fats (triglycerides or triacylglycerol):
3 fatty acids, each bonded to one of the three carbons on a glycerol molecule.
Glycerol
Fatty acids

17. A saturated fat Don’t eat too much!!!
Ester Linkages resulting from a condensation reaction
Don’t eat too much!!!

18. Types of fats…
Saturated fats – Fatty acid tails are completely saturated with hydrogens; there are no double bonds between carbons comprising the fatty acid tails.
Unsaturated fats – Fatty acid tails are incompletely saturated with hydrogens; one or more carbons comprising the fatty acid tails are double bonded together.

19. An unsaturated fat…
Double bond
Very “kinky” huh!

20. Saturated - vs - unsaturated fats

21. Why are unsaturated fats healthier than saturated fats?
The lack of double bonds in the fatty acid tails of saturated fats result in long, straight carbon chains.
Long straight carbon chains can clump together and attach to the walls of blood vessels.
These cause the buildup of atheroschlerotic plaque which can lead to disease such as…
Arteriosclerosis
Hypertension
Heart attack
Stroke

22. Unsaturated fats are healthier because…
the double bonds of unsaturated fats result in “kinks” in the fatty acid tails.
these kinks in the molecule reduce “clumping” of fat molecules in blood vessels.
this minimizes the buildup of atheroschlerotic plaques

23. Functions of fats…
Energy storage
Insulation
Protection

24. They have both a hydrophilic
More lipids…
Phospholipids
diglycerides
Phosphate group
Glycerol
Phospholipids are amphipathic molecules…
They have both a hydrophilic
and
hydrophobic region.
Fatty Acids

25. When phospholipids are placed in water, they will spontaneously aggregate into a bilayer…

26. Where in a cell can we find phospholipids?
the plasma membrane (outer membrane)
membranes surrounding organelles

27. Many lipids are steroids….
carbon skeleton is composed of 4 carbon rings with various functional groups attached.
Steroids are hydrophobic – they do not dissolve in water, but they are soluble in lipids.

28. Functions of steroids…
Hormones – signaling molecules of the endocrine system (i.e. sex hormones)
Cholesterol – important component of cell membranes - helps maintain membrane fluidity