fatty acids and triglycerides Flashcards
what type of molecule is a lipid
macromolecule which contains elements carbon, hydrogen, oxygen.
are lipids soluble in water
no insoluble as not polar but do dissolve in alcohol.
Three lipid molecules should know
1)Triglycerides
2)Phospholipids
3)Cholesterol
what type of molecule is a triglyceride
-macromolecule
-formed from 1 glycerol and 3 fatty acid molecules joined by ester bond
is the glycerol in a triglyceride always the same
yes
are the fatty acids in glycerol always the same
-no, there is 100s of fatty acids,
-made up of a carboxyl group with hydrocarbon tail
what can a hydrocarbon tail be
saturated or unsaturated and can vary in length
what is the difference between a saturated and unsaturated tail
-saturated all C-C bond are single
-Unsaturated at least one C=C double bonded
what is the bond between a glycerol and fatty acid
an ester bond
what is a glycerol made of
3 carbon alcohol molecule
what is an ester bond
formed when organic acid joins to alcohol molecule via condensation reaction
how long can the hydrocarbon tail be
2-20 carbons long and represented by R
how are triglycerides synthesised
-Both glycerol and fatty acids contain hydroxyl groups
-The groups interact leading to formation of 3 water molecules and bonds between glycerol and fatty acids
-this process is called esterification
what is a esterification reaction an example of
a condensation reaction
how can you reverse the reaction used to from a triglyceride
3 water molecules need to be supplied to reverse it
what is the reversal of a triglyceride formation reaction an example of
a hydrolysis reaction
in a fatty acid the R group hydrocarbon tail is what
variable
what is a hydrocarbon
chain of carbon atoms bonded together with hydro atoms bonded on each side of carbon
where are phospholipids present
in all bio membranes
what do phospholipids have a similar structure to
triglycerides but fatty acids replaced by phosphate group
what type of reaction is required to make a phospholipid
A condensation reaction
how is the ester bond formed in a phospholipid
reaction between OH group on a phosphoric acid and one of three -OH groups on glycerol form ester bond
what are the fatty acids in a phospholipid like
-even number (usually 16/18)
-usually one chain saturated other unsaturated
how is a phospholipid formed
inorganic phosphate ions in cytoplasm negatively charged (extra electrons). This ion replaces fatty acid in triglyceride making phospholipid.
is the fatty acids in a phospholipid hydrophobic or hydrophilic
hydrophobic
is the phosphate in a phospholipid hydrophobic or hydrophilic
hydrophilic
what is functions of lipids
-membrane formation
-hormone production
-electrical insulation
-waterproofing
how are triglycerides energy sources
-broken down in respiration to release energy/generate ATP
how are triglycerides broken down to be used as an energy source
hydrolyse ester bonds, then means both glycerol and fatty acids can be broken down to Co2 and H2O.
what produces more energy? sugar or a lipid
lipid produce more energy than when sugar respired
