lipids Flashcards
what do all lipids contain ?
hydrocarbons
What reaction forms a triglyceride ?
A condensation reaction
What type of molecule is a triglyceride
A lipid
What are fatty acids tails made of ?
Hydrocarbons
What is the structure of a triglyceride ?
1 glycerol attached to 3 fatty acids
What are the tails of a triglycerides (in terms of water )?
Hydrophobic
What do the tails do to aide triglycerides in their function ?
Tails make lipids insoluble in water
Do fatty acids all have the same structure ?
They all have the same basic structure but the hydrocarbon tails varies
What is the basic structure of a fatty acid ?
O =C-R
HO/
Carbon atom links fatty acid to glycerol
A variable R group hydrocarbon tail
Oxygen double bonded to carbon
Hydroxide single bonded to carbon
Carbon single bonded to Variable R group
What happens in the reaction to form a triglycerides?
Condensation reaction .fatty acid joins to glycerol molecule by an ester bond .An molecule of water is released .
This happens 2x times more to form a triglyceride.
What is the structure of glycerol
H
|
H-C-OH
|
H-C-OH
|
H-C-OH
|
H
Where are phospholipids found ?
Found in cell membranes
What is the structure of a phospholipid ?
One phosphate ,one glycerol and two fatty acid .
By etser bond
Describe the structure of a phospholipid (including the properties )
Phosphate group is hydrophilic
Fatty acid tail is hydrophobic
What the long hydrocarbon tail of fatty acids contain ?
Lots of chemical energy
What happens to the energy when you break down a triglyceride ?
It gets released
How much energy is released when a triglyceride is broken down ?
2x as much as carbohydrates
What is one feature of a triglyceride?
It’s soluble
Why is a triglyceride being soluble important with cells ?
Because it prevents it affecting the water potential of the cell because water entering the cell by osmosis would cause it to swell
It clumps together as insoluble droplets in cells so hydrophilic acid tails face inwards and SHEILD themselves from water using glycerol heads
what is the difference between a saturated and unsaturated fatty acid ?
Saturated fatty acids don’t have any double bonds between their
carbon atoms. The fatty acid is ‘saturated’ with hydrogen.
Unsaturated fatty acids do have double bonds between
carbon atoms, which cause the chain to kink.
describe the emulsion tests for lipids ?
Shake the test substance with ethanol for about a minute,
then pour the solution into water.
Any lipid will show up as a milky emulsion
The more lipid there is, the more noticeable the milky colour will be.
