Lipids Flashcards
2 distinguishing features of lipids
non-polar and hydrophobic
What is a fatty acid made of
Hydrocarbon chain with a carboxy at the end
2 features that change the Tm of a fatty acid - what forces are stronger
The length of the hydrocarbon chain
Whether the chains are saturated or not
VDW interactions
what are the 2 forms of unsaturated fats
Cis and Trans
What is a structural isomer
Molecules that have the same molecular formula but differ in the order that individual atoms are bonded
What is hydrogenation
removal of double bonding in poly-unsaturated fatty acids
2 reasons why lipids are good storage molecules
yield twice as much energy
Not hydrated so there is no extra weight of water
How are fatty acids anabolised and catabolised
C - process of beta-oxidation
A - Fatty acid synthase from carbohydrates
What makes up a triacylglycerol - what bond?
Glycerol + 3 ester linkage to 3 fatty acids
Why are fats solid at room temperature but oils are liquid
Fats are composed of saturated fatty acids whereas oils are unsaturated fatty acids
Where is TAG stored - what tissue does it make up
Adipocytes - Adipose tissue
What breaks down TAG - why do you need 3 for each molecule
Lipase - Each enzyme is specific for each carbon on glycerol
When is lipase released
When blood sugar is low
5 parts of a phosphlipid
Glycerol, unsaturated fatty acid, saturated fatty acid, phosphate group, variable group
Why can phospholipids not form micelles - what do they form instead
presence of an unsaturated fatty acid - a bilayer
What is another word for a lipid vesicle
A liposome
Give 2 ways phospholipids can move within the bilayer
Flip-flop
Lateral diffusion
The distribution of lipids varies between inner and outer leaflets so what are PMs said to be
Asymmetrical
Difference between glycolipid and a phospholipid
The variable group in a glycolipid is a sugar
4 functions of the bilayer
Formation of a barrier
Control of entry and exit of molecules
Provides shape
Cell to cell adhesion
3 types of proteins within the PM
Integral, peripheral and lipid-anchored
Term for the region of an integral protein that is in the bilayer
Trans-membrane domain
Name of the pumps used in AT across the membrane
ATPases
