1. Concept 5.3: Lipids include fats and steroids.

2. Lipids Group of organic compounds that include fats, oils, and waxes. Composed of carbon, hydrogen, and oxygen. No definite ratio of hydrogen atoms to oxygen atoms. All lipids are hydrophobic.

3. Building Blocks of Fats 1 glycerol molecule 3 fatty acids

4. Functions of Fats 2 Primary functions 1. Long term storage of energy 2. Building of structural parts of the cell. example: phospholipid bilayer

5. 2 types of fatty acids 1. Saturated - solids at room temperature -formed from fatty acids with single carbon to carbon bonds. C-C-C-C-C-C-C -Examples: butter, lards, fats from meats 2. Unsaturated - liquids at room temperature -formed from double carbon to carbon bonds C=C-C-C-C-C-C -Example: oil, vegetable oil, olive oil

6. Saturated vs. Unsaturated Fatty Acids unsaturated saturated

7. Steroids A lipid molecule in which the carbon skeleton forms four fused rings. Classified as lipids because they are hydrophobic, but different from fats in structure and function.