Lipids Flashcards
what are triglycerides
macromolecules
made up of 1 gycerol
attached to 3 fatty acids( made up of hydro carbons)
what is a special feature about the fatty acid tails
they are hydrophobic- making lipids insoluble in water
glycerol and fatty acids join together to form what type of bond??
how can triglycerides be broken down
Ester bond
which is formed by a condensation reaction( water molecule is released)
when ester bonds break in hydrolysis
how to differentiate between the 2 types of fatty acid
saturated has single C-C
unsaturated has double C=C
Difference between triglycerides and phospholipids
one of the fatty acids is replaced with a phosphate group
which is HYDROPHILLIC
tails are hydrophobic
why is triglyceride good for energy storage?
2 reasons
1) long fatty acid tails contain a lot of chemical energy(more than carbohydrates) meaning loads more energy can be released when broken down.
2) INSOLUBLE- so don’t affect water potential.
how are triglycerides arranged
the bundle up as insoluble DROPLETS in cells
because the fatty acid tails are hydrophobic- so they face inwards shielding themselves from water
glycerol heads face outwards( hydrophillic)
where are phosholipids found
in the cellmembrane as they make up the phospho lipid bilayer
how are phospholipids arranged
form a double layer with the heads facing outwards towards water on either sides
how can the bilayer act as a barrier to water soluble substances
the CENTRE of the bilayer is hydrophobic- so water soluble substances can not easily pass through it
what is the function of cholesterol in eukaryotic cells
to helps strengthen the membrane by interacting with the phospholipid bilayer
how does cholesterol look and why is this good
small in size
flattened shape
allowing it to fit in between phospholipid molecules in the membrane
how can cholesterol make the membrane less fluid and more rigid
They bind to hydrophobic tails of the phopholipids causing them to pack more closely together
