Lipids: 2003-2004

Concentrated energy molecules Lipids Concentrated energy molecules

Lipids Examples Triglyclerides Waxes Phospholipids a) Oils- liquids at room temp B) Fats- solids at room temp Waxes Phospholipids Sterols- (lipid hormones) sex hormones testosterone (male) estrogen (female) 2003-2004

Lipids Function: energy storage (triglycerides) cell membrane very concentrated twice the energy as carbohydrates! Animals convert excess carbohydrates into fat cell membrane (phopsholipids) cushions organs insulates body think whale blubber! 2003-2004

Structure of Fatty Acid Nonpolar chain Polar End

Forming Triglyceride not a chain (polymer) = just a “big fat molecule”

Structure of Triglyceride not a chain (polymer) = just a “big fat molecule” 3 fatty acids 1 glycerol Ester link

Saturated fats Most animal fats Limit the amount in your diet solid at room temperature Limit the amount in your diet contributes to heart disease deposits in arteries

Unsaturated fats Plant, vegetable & fish fats liquid at room temperature the fat molecules don’t stack tightly together Better choice in your diet

Saturated vs. unsaturated  2003-2004

Hydrogenated Fats Industrial process Adds hydrogen atoms to the double bonds in unsaturated triglyceride (liquid fats, ie. Canola oil) Converts them to semi-solid fats (ie. Margarine or shortening)

Other lipids in biology Cholesterol good molecule in cell membranes make hormones from it including sex hormones but too much cholesterol in blood may lead to heart disease 2003-2004

Other lipids in biology Cell membranes are made out of lipids phospholipids heads are on the outside touching water “like” water tails are on inside away from water “scared” of water forms a barrier between the cell & the outside 2003-2004