Lipids🧈 Flashcards
What are lipids?and examples
Lipids are a diverse group of organic compounds that are insoluble in water but soluble in organic solvents.
include fats, oils, phospholipids, and steroids.
State lipids functions
energy storage, cell membrane structure, insulation, and signaling.
What the 2 group of lipids?
Triglycerides and phospholipids
What is the difference between triglycerides and phospholipids?
Triglyceride has 3 fatty acids joined to a glycerol molecule
Whilst phospholipids has 2 fatty acids attached to glycerol and a phosphate group attached to glycerol.
How is triglycerides formed?
Condensation of 3 molecules of fatty acids and 1 molecule of glycerol.
Forming water and an ester bond
It is C-O-C=O
What does the R group mean in fatty acids?
Means it Can be saturated
when single bonds are present between molecules carbon only.
Unsaturated
The hydrocarbon chain has at least one double bond between carbons only.
State the properties of triglycerides.
Energy storage-due to the high ratio between energy-storing carbon-hydrogen bonds than in carbon so a lot of energy can be stored.
Acts as a metabolic water source:as there is more hydrogen to oxygen,can release water if oxides (lose or gain of electrons)essential for animals in deserts like camels by having a hump of triglycerides .
Because they are big and hydrophobic makes them insoluble so they don’t affect water potentials.
Relatively low mass so a lot can be stored without increase of mass and preventing movement.
Describe the emulsion test for lipids.
Add lipids to test tube add ethanol to help dissolve the sample being tested. with goggles and add distilled water
in to avoid introducing impurities or contaminants that could interfere with the test results.
if white emulsion appears there is a lipids
Emulsion:splitted parts
How is a phospholipids made?
1 glycerol attached to 2 fatty acids via condensation reaction resulting in 2 esters bond,and a phosphate group with glycerol.
Give phospholipids properties.
Head is charged and it is hydrophilic
Due to phosphate group being charged it repels other fats
Tails is hydrophobic will mix with fats
Have 2 charged regions so they are polar forming a bilayer (c.m)
What is the test for starch?
Add iodine
Positive solution from orange to blue/black
Give me protein test
Add biuret
Positive from blue to purple
What are enzymes?
They are a tertiary structure of proteins
Which catalyse reactions.
Which has a active site complementary to substrate.
What does an enzyme do to a reaction?
When enzyme attach to substrate there is a lower activation energy
So there is a speeds up of reaction and without there is a high activation energy (minimum amount of energy needed to start a reaction)
