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 What is the function of a triglyceride? 1. Stores and transfers genetic information 2. Long term energy storage 3. Control the rate of reactions 4. Help to fight disease

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

AP Biology Fats that have at least one double bond between Carbon atoms are called 1. Unsaturated 2. Saturated 3. Glycerol 4. Fatty Acids

AP Biology Phospholipids have a 1. hydrophobic head and hydrophilic tail 2. hydrophilic head and hydrophobic tail

AP Biology Which of the following is an example of a steroid 1. Fatty acids 2. Sex hormones 3. Phospholipids 4. Olive Oil