LIPIDS

1. LIPIDS

2. LIPIDS • Fats, oils, phospholipids, steroids & waxes • Composed of C, H, O (but fewer O than carbs) • Chains of C atoms bonded to each other and to H atoms.

3. Lipids are HYDROPHOBIC! “Water fearing”(b/c of non-polar C-H bonds in the tail)

5. 3 Major Roles of Lipids: #1: Used as long-term energy storage. Adipose cells: (fat cells) store energy, cushion vital organs, and insulate the body.

6. Fats store energy more efficiently than carbs. (They have more H bonds!) • Many organisms can survive w/o steady diets because of stored fat. When there’s lots of food, animals convert excess food into fats. When food is scarce, these can be broken down for energy.

7. #2: Form biological membranes & control water movement. • Cell membranes are made up of phospholipids. One end likes water, one end is repelled by water. • Waxy surface on plants controls water loss.

8. #3: Used as chemical messengers. • Ex. Steroids (testosterone & estrogen) Testosterone

9. MONOMERS • Lipids are made up of fatty acids • Fatty Acids - long chains of C & H atoms that have a carboxyl group (-COOH) at one end. - polar - hydrophilic  “water loving” • Have a hydrocarbon group at the other end (CH3) • Nonpolar • Hydrophobic

10. Saturated Fats= All C atoms are bonded by a single bond, holding the max number of H atoms. • Commonly found in dairy products and meats.

11. Unsaturated Fats = A pair of carbon atoms is joined by a double bond, it doesn’t contain the max number of H atoms. • Changes the shape, by adding a “kink”

13. Polyunsaturated = Contains multiple double bonds. Will be oil at room temp, such as peanut and corn oil.

14. Phospholipids • Consist of hydrophilic and hydrophobic regions. • Made up of only two fatty acids, instead of three. • Make up cell membranes.