3.2.1.3
Lipids
• insoluble in water, soluble in organic solvent (e.g. ethanol)
• room temp fats = solid, oils = liquid
Triglycerides
• held together by ester bonds
• fatty acids = long hydrocarbon chains
• can be saturated/ unsaturated (1+ double bonds between C)
• glycerol: fatty acid:
R.COOH
• formation:
condensation
triglyceride + water
Properties
• ↑ energy storing C-H bonds : C atoms :. good energy source
• ↓ mass : energy :. good storage
• insoluble in H₂O :. x a ect water potential
• ↑ H:O₂ :. release H₂O when oxidised :. H₂O source
Lipid Emulsion Test
• crush small amonunt of test sub in dry, grease free test tube
• mix w. ethanol + shake
• lter + collect ethanol solution
• add water
• lipid = white emulsion
Phospholipids
• polar
• mix w. water arrange self in double layer w. hydrophobic tails pointing
in + hydrophilic heads pointing out = phospholipid bilayer hydrophilic hydrophobic
• structure allows formation of glycolipids by combing w. carbs in cell-
surface membrane (important in cell recognition)
fi
ff
Lipids
• insoluble in water, soluble in organic solvent (e.g. ethanol)
• room temp fats = solid, oils = liquid
Triglycerides
• held together by ester bonds
• fatty acids = long hydrocarbon chains
• can be saturated/ unsaturated (1+ double bonds between C)
• glycerol: fatty acid:
R.COOH
• formation:
condensation
triglyceride + water
Properties
• ↑ energy storing C-H bonds : C atoms :. good energy source
• ↓ mass : energy :. good storage
• insoluble in H₂O :. x a ect water potential
• ↑ H:O₂ :. release H₂O when oxidised :. H₂O source
Lipid Emulsion Test
• crush small amonunt of test sub in dry, grease free test tube
• mix w. ethanol + shake
• lter + collect ethanol solution
• add water
• lipid = white emulsion
Phospholipids
• polar
• mix w. water arrange self in double layer w. hydrophobic tails pointing
in + hydrophilic heads pointing out = phospholipid bilayer hydrophilic hydrophobic
• structure allows formation of glycolipids by combing w. carbs in cell-
surface membrane (important in cell recognition)
fi
ff
