lipids

Question 1

what is the general formula of a lipid?
lipids are fats and oils so how is it in relation to water?
how is a triglyceride made?
how many condensation reactions occur?
what are the components of a phospholipid?
note: r groups are the fatty acids
saturated meaning:
unsaturated meaning:

Answer 1

• RCOOH
• insoluble
• formed by a condensation reaction between 1 molecule of glycerol and 3 molecules of fatty acid where 3 water molecules and 3 ester bonds are produced
• 3 SEPARATE condensation reactions
• 1 phosphate group, 1 molecule of glycerol, 2 molecules of fatty acids
• the hydrocarbon chain consists of only single bonds between the carbons
• the hydrocarbon chain consists of at least one double bond between carbons

Question 2

what are the properties of triglycerides (4)
test for lipids:
what is the phosphate group attached to in a phospholipid?
what are the fatty acids bound to in a phospholipid?
how many condensation reactions and ester bonds in a phospholipid?

Answer 2

• energy storage:
  large ratio of energy storing carbon - hydrogen bonds
• high ratio of H:O atoms which can be used as a metabolic water source that can release water
• large and hydrophobic and so insoluble in water meaning it doesn’t affect water potential
• low mass so lots can be stored without increasing the mass
• dissolve sample in ethanol
• mix
• add distilled water
• white emulsion - lipid
• attached to glycerol
• glycerol
• 2

Question 3

what are the 2 main properties of a phospholipid?
how are the bits and bobs positioned and what do we call the structure of this?

Answer 3

• hydrophilic head (phosphate group) attracted to water as it is charged
• hydrophobic tails (fatty acid CHAINS) not attracted to water and will repel water bc it isn’t charged
• the heads are exposed to water and the tails are protected forming a phospholipid bilayer membrane structure