Biology and Human Concerns09/28/09

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.

alphaomega

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.

“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 bilayerSteroids-Cholesterol and hormonal properties