lipids Flashcards
What are the components of triglycerides?
- A glycerol molecule.
- 3 fatty acid chains.
What are the components of phospholipids?
- A glycerol molecule.
- A phosphate group.
- Two fatty acid chains.
How are triglycerides formed? What is produced as a by-product of this reaction?
- Triglycerides are formed via the condensation of one molecule of glycerol and 3 molecules of fatty acid (ie. three different condensation reactions occur.)
- 3 molecules of water are produced by this condensation reaction.
Atoms involved in ester bond?
– COO
Explain what happens to glycerol and fatty acids in a condensation reaction to make a triglyceride + 3 water molecules.
- Ester bond formed by condensation reaction between three OH groups on glycerol and the OH group of each fatty acid chain (releasing 3 molecules of water, leaving 3 ester bonds on triglyceride.)
What are the 2 groups of lipids?
- Phospholipids.
- Triglycerides.
What is the general formula of a fatty acid?
- (RCOOH)
- (R means varibale group - the number of carbons and hydrogens can change.)
() - extra for clarification
FInish the sentence.
The R group of a fatty acid can be ……… or ……….
- Saturated
- Unsaturated.
Definition of: saturated fatty acids.
- The hydrocarbon chain has only single bonds between carbons.
Definition of: unsaturated fatty acids.
- The hydrocarbon chain consists of at least one double bond between carbons.
In phospholipids, what are one of the fatty acids of the triglyceride substituted by.
- Substituted by a phosphate- containing group.
Why do triglyceride’s structure help them store energy well?
- Due to the large ratio of energy-storing carbon-hydrogen bonds compared to the number of carbon atoms.
(those carbon-hydrogen bonds store a lot of energy.)
() - extra info for clarification.
What structure do triglyceride’s have that allow them to be a “metabolic water source?”
- Molecules have a high ratio of hydrogen to oxygen atoms - act as metabolic water source.
- Triglycerides can release water when oxidised (essential for animals in desert.)
What is meant when we say triglycerides are non-polar molcules, how does this help them?
- Triglycerides non-polar (have no chargee) making them insoluble in water (also because they are large= insoluble.)
- A large amount can be stored/ won’t affect water potential. No osmosis of water into cell.
Why is it useful that lipids have a relatively low mass?
- Helps with them being energy-storage molecules.
- A lot of molecules can be stored without increasing the mass/ preventing movement.