Lipids

:3

Steroids and modified fatty acid

cholesterol; hormones and vitamins

Carotenoids and chlorophylls

capture light energy in plants

Animal fats

saturated: packed together tightly (straight); solid at room temperature.

Plant oils

unsaturated: the “kinks” prevent packing; liquid at room temperature.

Amphiphatc

have opposing chemical properties (fatty acids)

Carboxyl group ionizes

forms COO– and is strongly hydrophilic; the other end is hydrophobic.

Phospholipids

fatty acids bound to glycerol; a phosphate group replaces one fatty acid.

Steroids

multiple rings share carbons

Cholesterol

a steroid that reduces permeability of lipid membranes, restrict the passage of molecules by increasing the packing of phospholipids

xanthophylls

carotenoid that contains oxygen (yellow)

carotenes

carotenoid that are hydrocarbons and do not contain oxygen (orange)

Micelle

formed by self-assembly of amphiphilic molecule (soap/detergent)

Why are lipids high in energy?

high concentration of carbon-hydrogen bonds which store a lot of potential energy, can be released when broken down during cellular respiration.

Lipid coating around nerves

provides electrical insulation

Neutral fats (triglyceride)

fat group that is uncharged and do not contain acidic or basic groups

Ester Linkage

Carboxyls bond with hydroxyls of glycerol

Glycerol

3 —OH groups (an alcohol)

Fatty acid

nonpolar hydrocarbon with a polar carboxyl group