Lipids

Lipids are composed of:

• Carbon

• Hydrogen

• Oxygen

BUT: Lipid molecules have a larger number of Carbon and Hydrogen and a smaller number of Oxygen than Carbohydrates

“CHO”

Lipid Functions

• Lipid molecules provide a barrier b/t a cell and its watery environment

Lipid Functions

• Insulation of whales and walruses

Lipid Functions

• Skin oils help repel water from feathers of ducks

Lipid Functions

• Waxy layer of plants, keeps water in

Fatty Acids• Lipids are composed of building blocks or

MONOMERS called Fatty Acids.Yellow

Pink/Red

Fatty Acids

• Carboxyl end (-COOH)– polar– Hydrophilic: “water loving”

– Hydrocarbon end (CH3)

• Non-polar• Hydrophobic: “Water fearing”

WATER

Arrangement of FA in Cell

Functions of Lipids

• Store Energy!!

• Fats have more H bonds than Carbs and can store more energy.

Kinds of LIPIDS

1. Triglycerides

2. Waxes

3. Steroids

4. phospholipids

Triglycerides

Composed of:

1. 1 glycerol molecule

2. 3 molecules of fatty acids

TWO categories of triglycerides

1. Saturated

2. unsaturated

Waxes

• Plant waxes– Forms protective

coating on outer surface

• Earwax– Prevents bacteria from

entering middle ear

Steroids

• Composed of 4 carbon rings

• Found :– Hormones– Toad venom– Plant poisons– Chlorophyll– Cholesterol

THE END