Lipids Flashcards
what are some types of lipids? (5)
fats, oils, phospholipids, waxes, steroils
what differs in fats and oils?
melting point
where are they found?
animals and plants
what are some uses of lipids (8)?
insulates - under the skin, reduces thermal transfer
energy store is 3-5 times more energy from lipids than ATP
oils on skin and hair to keep supple
lubricant in joints
hormones
cell membrane
insoluble - not very soluble
insulates neurons
what are lipids made up of?
1 glycerol and 3 fatty acids
what are the three sections of a fatty acid?
carboxylic acid, hydro-carbon, methyl group
what does saturated mean?
it means a fatty acid with NO c-c double bonds
what does unsaturated mean?
when a fatty acid has a c-c double bond (mono unsaturated) or two c-c double bonds (poly saturated)
what do less hydrogen bonds mean?
in unsaturated fatty acids there are less hydrogen bonds making it unstable
what takes place to form a triglyceride?
3 condensation reactions (3 molecules of water is lost/produced)
what is the name of the bond formed?
an Esther bond
when triglycerides are hydrolysed how many monomers are produced and what are they?
4 monomers! 1 glycerol and 3 fatty acids
what are monoglycerides and diglycerides?
monoglycerides = 1 glycerol and 1 fatty acid
diglycerides = 1 glycerol and 2 fatty acids
what do diglycerides have and how does this help them carry out their function?
as they have 2 fatty acids they have an empty ‘port’ and a phosphate bonds to create a phospholipid which makes up the cell membrane
what characteristics do glycerol and fatty acids have?
fatty acids - are hydrophobic
glycerol - polar/hydrophilic
why does the phospholipid representation have a kink in it?
it’s kinked because of the c=c double bond which makes it mono-unsaturated
what is the structure of the cell membrane?
they have phosphate hydrophilic heads which means they’re soluble however their tails are hydrophobic (a.k.a insoluble) this creates a bilayer of cell membranes. The centre of the bilayer is hydrophobic so water-soluble substances can’t easily pass through as the fatty acids and water would separate and destroy the cell the membrane acts as a barrier to those substance
