What is better for your health: Butter, Margarine, Olive Oil or Crisco? LG: Understand the structure and function of different types of lipids.

9/25 QOD: How is a saturated fatty acid different from an unsaturated fatty acid? Draw each! LG: Understand the structure and function of different types of lipids.

Intro to Organic Molecules & Lipids

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 Carbon chemistry = organic chemistry Why is it a foundational atom? What makes it so important? Can’t be a good building block if you only form 1 or 2 bonds. H C

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 Made of same elements as carbohydrates but very different structure/ proportions & therefore very different biological properties

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

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 Mostly animal fats

Unsaturated fats At least one C=C double bond in the fatty acids plant & fish fats vegetable oils liquid at room temperature Mostly plant lipids Think about “natural” peanut butter: Lots of unsaturated fats Oil separates out Companies want to make their product easier to use: Stop the oil from separating Keep oil solid at room temp. Hydrogenate it = chemically alter to saturate it Affect nutrition?

Saturated vs. unsaturated 

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)

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

Testosterone

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

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

Which type of lipid makes up the majority of the cell membrane? phospholipids waxes steroids triglycerides

Fats that have at least one double bond between Carbon atoms are called Unsaturated Saturated Glycerol Fatty Acids

Phospholipids have a hydrophobic head and hydrophilic tail hydrophilic head and hydrophobic tail

Which of the following is an example of a steroid Fatty acids Sex hormones Phospholipids Olive Oil