1. Lipids
Fats, Oils, waxes

2. Lipid Basics Made of C,H,O monomer = glycerol + fatty acids
hydrophobic - don’t dissolve in water
oil and water don’t mix

3. Fatty Acids 2 types – saturated and unsaturated
- What’s the difference?
- saturated fatty acids
No double bonds between C atoms
- holds the maximum # of H atoms
- unsaturated fatty acids
contain double bonds between C atoms

4. Lipids- Fats and Oils
Fats & Oils (triglycerides)- long term energy storage
Fat has twice the calories of carbohydrates.
fat = 9 cal/g sugar= 4 cal/g
Health tip:
Saturated or hydrogenated fats(bad) vs. unsaturated (good)
2-24

5. Lipids: types and functions
Fats/Oils – long term energy storage, insulation and protection
Phospholipids – cell membranes
Steroids – make hormones (chemical messengers)
Waxes – waterproofing

6. Saturated fat and fatty acid
Fats (Saturated)
Solid at room temperature
Energy storage in animals
contain saturated fatty acids
Saturated fat and fatty acid
Stearic acid

7. Body Fat – stores energy, insulates and protects the organs
Excess energy is converted to fat
Sea mammals rely on fat to keep them warm

8. Unsaturated fat and fatty acid
Oils (Unsaturated)
energy storage in plants
contain unsaturated fatty acids
liquid at room temperature
Unsaturated fat and fatty acid
Double bond
causes molecule
to bend
Oleic acid

9. Phospholipids- create the structure of cell membranes
only 2 fatty acids (not 3 like fats and oils)
3rd fatty acid is replaced by a phosphate molecule
SPONCH

10. (a) Structural formula (b) Space-filling model
Phospholipid structure
Phosphate molecule forms a hydrophilic (water loving) head
Fatty acid molecules make up a hydrophobic tails
CH2 O P CH C
Phosphate
Glycerol
(a) Structural formula
(b) Space-filling model
Fatty acids
(c) Phospholipid
symbol
Hydrophobic tails
Hydrophilic
head
Hydrophobic
tails –
Hydrophilic head
Choline +
Figure 5.13
N(CH3)3 10

11. myelin - phospholipid that insulates nerve cells
We are all literally “Fatheads”

12. Cholesterol
component of cell membrane
used to make steroids

13. Steroids: Lipids that act as Hormones
Hormones are chemical messengers
- produced in one part of the body, they travel to and
cause changes in another part of the body
- Hormones control:
growth
development
tissue function
sexual function
the way our bodies use food,
the reaction of our bodies to emergencies,
mood
- examples
estrogens
testosterone
Estrogen Testosterone

14. Waxes-Lipids that repel water
- found on the surface of leaves
- found on animal hair to keep it pliable
- found on the feathers of water birds to prevent them from becoming waterlogged