AP Biology Intro to Organic Molecules & Lipids

AP Biology Life is based on Carbon Carbon atoms are versatile building blocks Special bonding properties Has 4 valence electrons so it can form 4 stable covalent bonds with other carbon atoms or atoms of other elements Bonds with CHNOPS – the elements that make up living things; Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, and Sulfur H H C H H

AP Biology Lipids Lipids are organic molecules essential for life that are composed mostly of C, H, O 4 types of lipids fats (triglycerides) phospholipids steroids waxes

AP Biology Triglycerides Fat molecules Structure = 3 fatty acids chains linked to glycerol Functions = long term energy storage and insulation for animals Can be saturated or unsaturated Glycerol 3 fatty acids

AP Biology Saturated fats All C bonded to H No C=C double bonds long, straight chain most animal fats and butter solid at room temperature contributes to cardiovascular disease

AP Biology Unsaturated fats At least one C=C double bond in the fatty acids plant & fish fats vegetable oils liquid at room temperature

AP Biology Saturated vs. unsaturated saturatedunsaturated

AP Biology Phospholipids Structure: 2 fatty acids chains + phosphate head Fatty acid chains = non-polar = hydrophobic “water fearing” Phosphate head = polar = hydrophillic “water loving” Function: make up cell membranes (phospholipid bilayer)

AP Biology Steroids Structure: 4 fused Carbon rings examples: cholesterol – Function =control the fluidity of the cell membrane hormones – Function = regulate processes in the body (such as pregnancy) vitamins (A, B, D) – Function = supports metabolism and cell processes

AP Biology Waxes Solid at room temp Insoluble in water Function: Protective covering for animals and plants Examples: Beeswax Earwax Cuticle of leaf (keeps water in)

AP Biology Which of the following is an example of a type of triglyceride? 1. A fat containing 3 saturated fatty acids 2. A fat containing 2 saturated fatty acids & 1 unsaturated fatty acid 3. A fat containing 3 unsaturated fatty acids 4. All of the above eufic.org aafp.org mpkb.org

AP Biology 2 Which of the following types of fats (triglycerides) would be an oil at room temperature and would be healthier to eat since its bent carbon & hydrogen chains and don’t stack well? 1. Unsaturated fat WITHOUT any C to C double bonds 2. Saturated fat WITHOUT any C to C double bonds 3. Unsaturated fat containing C=C 4. Saturated fat containing C=C 5. Steroids like testosterone hormone or cholesterol eufic.org aafp.org mpkb.org

AP Biology 3 Which type of lipid makes up the majority of the cell membrane? 1. phospholipids 2. waxes 3. steroids 4. triglycerides essortment.com alevelnotes.com

AP Biology 4 Phospholipids contain: 1. A hydrophobic polar phosphate head & 2 hydrophilic nonpolar fatty acid tails 2. A hydrophilic polar phosphate head & 2 hydrophobic nonpolar fatty acid tails ne.gif

AP Biology 5 Which is an example of a steroid? 1. Fatty acids 2. Sex hormones 3. Phospholipids 4. Olive Oil 5. Triglycerides Structure of triglycerides: fats & oils Structure of sex hormones

AP Biology 6 What is the function of a triglyceride? 1. Stores and transfers genetic information 2. Long term energy storage, as well as insulation & protection 3. Control the rate of reactions 4. Help to fight disease

AP Biology 7 What is the function of hormones such as the steroid hormones? 1. Communication & cooperation between cells 2. Short term energy storage 3. Structural building materials 4. Compose the bilayer cell membrane

AP Biology 8 What is the cholesterol considered a steroid? 1. They have a similar hydrophobic structure 2. The both contain rings made mostly of Carbon and Hydrogen atoms 3. They are both nonpolar covalent 4. All of the above cholesterol