Lipids Flashcards
Roles of lipids
-source of energy
-waterproofing
-insulation
-protection
What are the main categories of lipids
triglycerides and phospholipids
Whats the general structure of a triglyceride
Molecule of glycerol joined to 3 fatty acid molecules
What are the two key parts of fatty acid molecules
At the end we have a carboxylic group
The rest consists of a long chain of carbon atoms bonded to hydrogen atoms
(Saturated fatty acid)
Difference between saturated fatty acids and unsaturated fatty acids
saturated fatty acids contain only single covalent bonds between the carbon atoms and unsaturated fatty acids contain at least one double covalent bond between the carbon atoms
Whats it called when there’s only one double covalent bond in the carbon chain
monounsaturated
Whats it called when there’s more than one double covalent bond in the carbon chain
polyunsaturated
What does a glycerol molecule have
3 hydroxyl groups
What bond is formed between glycerol and fatty acids
Ester bond (esterfication)
What type of reaction is the bonding of a glycerol molecule to a fatty acid molecule
condensation
How do you break the ester bonds (+ what reaction)
lipase enzymes break them in the digestion system (hydrolysis reaction)
Key points to tryglyceride (2)
They are non-polar (hydrophobic- do not dissolve in water)
As they have a large number of carbon and hydrogen atoms, they are an excellent source of energy
Structure of a phospholipid
One glycerol bonded to 2 fatty acids, the glycerol is also bonded to a phosphate
Why is the phosphate group hydrophilic
As its a polar molecule, negatively charged
What is meant by hydrophilic
Attracts water molecules, water loving
What does the phospholipid bilayer consists of
The hydrophilic (polar) head group and hydrophobic tails (fatty acid chains)
Why is the phospholipid billayer important
Allows phospholipids to create membranes
relate the structure of triglycerides to their function
-good energy store (fatty acid tail)
-insoluble (waterproofing)
describe the functions and structure of phospholipids
-1 glycerol, 2 fatty acids, phosphate group
-forms phopholipid bilayer
-tail allows for waterproofing
