09 28 09 Notes
- 1. Biology and Human Concerns 09/28/09 Lipids -Hydrophobic -Oils, fats, waxes -Fats – triacylglycerol -glycerol + three fatty acids -fatty acids + glycerol = ester bond Saturated Fatty Acids -Structural formula of a saturated fat molecule -Found in meat, animal protein Unsaturated Fatty Acids -Liquid at room temperature -Oils -Carbon double bond present in unsaturated fatty acids Cholesterol – replace animal fatty acids (saturated) with plant fatty acids (unsaturated). Good Fatty Acids? -All fatty acids have a carboxyl group at the “Alpha” end. alpha omega butyric acid -Essential fatty acids, not made in our bodies -Omega 3 and Omega 6 -Dark green leafy vegetables, flax, fish. -Help process HDL and LDL cholesterol. Decrease LDL, increase HDL.
- 2. “Trans” Fats -When plants or animals make unsaturated fats, they mostly build this kinked “cis” form. Oleic acid, cis form. Trans molecule – This hydrogenation process also converts the bent “cis” form to a straightened “trans” form, which looks like this: Exposure to prolonged heat (as in deep frying) also creates trans fats by loosening the double bond and allowing to flip into the straight form. Phospholipids -one head hydrophobic (non-polar end), one head hydrophilic (polar end) Phospholipid bilayer Steroids -Cholesterol and hormonal properties