variableR-group - hydrocarbonchain (saturated or unsaturated)
COOHgroup is a carboxylgroup
differences between saturated and unsaturated fatty acids
saturated has noc=cdoublebonds in hydrocarbonchain as allcarbons are fullysaturatedwithhydrogen
unsaturated has one or morec=cdoublebond in hydrocarbonchain (creatingbend/link)
describe how triglycerides form
1glycerolmolecule and 3fattyacids
condensationreaction
removing3watermolecules
forming3esterbonds
how the properties of triglycerides are related to their structure
highratio of C-Hbonds to carbonatoms in hydrocarbonchain
so used in respiration to releasemoreenergy than samemass of carbohydrates
hydrophobic/non-polarfattyacids so insoluble in water (clumptogether as droplets)
so noeffect on water potential of cell (or can be used for waterproofing)
difference between the structure of triglycerides and phospholipids
one of the fattyacids of a triglycerides is substituted by a phosphate-containinggroup
describe how the properties of phospholipids relate to their structure
phosphateheads are hydrophilic so are attracted to water so pointtowater (aqueousenvironment) either side of membrane
fattyacidtails are hydrophobic so repelledbywater so pointaway from water/tointerior of membrane
function of phospholipids
form a bilayer in cellmembrane, allowingdiffusion of lipid-soluble (non-polar) or verysmallsubstance and restrictingmovement of water-soluble (polar) or largersubstances