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”
Properties of Lipids • Fats, oils, and waxes are lipids. • Unlike the other organic compounds, lipids do not dissolve in water; therefore, they are nonpolar or insoluble.
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.
Fatty Acids • Carboxyl end (-COOH) • polar • Hydrophilic: “water loving” • Hydrocarbon end (CH3) • Non-polar • Hydrophobic: “Water fearing” WATER
Functions of Lipids • Store Energy!! • Fats have more H bonds than Carbs and can store more energy.
Kinds of LIPIDS • Triglycerides • Waxes • Steriods • phospholipds
Triglycerides Composed of: • 1 glycerol molecule • 3 molecules of fatty acids
TWO categories of triglycerides • Saturated • 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