Lipids

1 glycerol

3 fatty acid (hydrophobic tails)

3 ester bonds (glycerol and fatty acids bond during a condensation reaction and water is removed)

1 glycerol

2 fatty acid tails - non-polar

2 ester bonds

1 phosphate (hydrophilic so swivels round) - polar

Phospholipid-

in biological membranes

electrical insulation: in the myelin sheath around the axon of the nerve cells

Triglyceride-

Thermal insulation- lipids under the skin

protection - fats around internal organs like the kidneys

metabolic water

energy reserves in both plants and animals as they have more c-h bonds than carbohydrates

waxes-

waterproofing ie leaf cuticle and exoskeleton of insects

if the diet is high in saturated fats; low density lipoproteins (LDL) build up. atheromas(fatty material)(from the liver to the tissue) get deposited in the coronary arteries restricitng blood and o2 delivery to the heart = can result in angina

if the diet is high in unsaturated fats the body makes more high density lipoproteins (HDL) which carries harmful fats away from the tissue to the liver

the more hdl the better

Emulsion test

mixed with ethanol which dissolves lipids. shaken with water, the lipids come out of soultion as they are insoluble and form an emulsion = cloudy white