Lipids: Fats, Oils & Waxes Large and varied group Made up of mostly __ & __atoms (O too!) Do not dissolve in water Uses: Energy Storage Waterproofing Structure Hormones

Triglycerides function to cushion organs, as insulation & in long-term energy storage Made of two kinds of molecules _____________ Saturated Fatty Acid: Carbons joined by ______ bonds Maximum _________ atoms Unsaturated Fatty Acid: At least one ___________ bond between ________ in the fatty acid Triglycerides -glycerol, fatty acids single, hydrogen Double, carbons

Fatty Acids Fatty acids that contain 1 or more double bonds between carbon atoms are said to be ___________. Fatty acids with only single covalent bonds between the carbon atoms are referred to as ___________. Unsaturated, saturated

Note: many more C atoms than O atoms. Saturated fats - fatty acids are saturated with H atoms. There are no double-bonded carbons. Tend to be liquid at room temperature. Unsaturated - fatty acids are not completely saturated with H atoms (thus have 1 or more double bonded carbons). Double bonds cause kinks in the fatty acid tails. Tend to be solid at room temperature. Lipids in plants are less saturated than those in animals.

What are Trans fats? Trans fat is the common name for a type of unsaturated fat with trans-isomer fatty acid(s). Trans fats may be monounsaturated or polyunsaturated. Most trans fats consumed today are created industrially in partial hydrogenation of plant oils — a process developed in the early 1900s and first commercialized as Crisco in 1911. The goal of partial hydrogenation is to add hydrogen atoms to cis-unsaturated fats, making them more saturated. These saturated fats have a higher melting point, which makes them attractive for baking and extends their shelf-life. However, the catalyst also catalyses a side reaction that isomerizes some of the cis-unsaturated fats into trans-unsaturated fats instead of hydrogenating them completely. Another particular class of trans fats, vaccenic acid, occurs naturally in trace amounts in meat and dairy products from ruminants. Unlike other dietary fats, trans fats are neither essential nor salubrious[1] and, in fact, the consumption of trans fats increases one's risk of coronary heart disease[2] by raising levels of "bad" LDL cholesterol and lowering levels of "good" HDL cholesterol.[3] Health authorities worldwide recommend that consumption of trans fat be reduced to trace amounts. Trans fats from partially hydrogenated oils are more deleterious than naturally occurring oils.[4] Chemically, trans fats are made of the same building blocks as non-trans fats, but have a different arrangement. In trans fatty acid molecules, the hydrogen atoms are bonded to pairs of doubly bonded carbon atoms (characteristic of all unsaturated fats) in the trans rather than the cis arrangement. This results in a straight, rather than kinked, shape for the carbon chain, more like the straight chain of a fully saturated fat. Source: http://biology.clc.uc.edu/Courses/bio104/lipids.htm

Phospholipids Building block of _______ _______ Have Only has 2 _____________ 1 ____________ group Have Hydrophilic heads Hydrophobic tails Cell membranes Fatty acids phosphate

Steroids Carbon Skeleton has: Cholesterol Hormones Four interconnected rings Different groupings of atoms (or functional groups) attached Cholesterol Hormones