Lipids Flashcards
1
Q
What is a lipid
A
-a molecule containing carbon, hydrogen and oxygen
- fats/oils
2
Q
Are lipids soluble and polar?
A
- Non-polar molecules- the electrons in outer orbitals form bonds that are evenly distributed
- No positive or negative areas within the molecule
- insoluble in water
3
Q
What type of molecules are lipids built up of
A
- macromolecules
- (repeating units)
4
Q
What is a triglyceride
A
- made by combining 1 glycerol molecule and 3 fatty acid
- type of lipid
5
Q
What is glycerol
A
alcohol
6
Q
What is a fatty acid
A
- carboxylic acids
- consist of a carboxylic group with a hydrocarbon chain attached
7
Q
What is the bond formed between glycerol and fatty acids, what type of reaction
A
- ESTER bond
- CONDENSATION
- the glycerol and fatty acid hydroxyl groups interact, leading to the formation of 3 water molecules
- esterification reaction
8
Q
What is a saturated lipid
A
- no double C bond
- no C=C, C-C only
9
Q
What is an unsaturated lipid
A
- double bonds between at least one pair of C atoms
- C=C present
10
Q
What are monounsaturated lipids and polyunsaturated lipids
A
- mono= q double bond
- poly= 2 or more double bonds
11
Q
What is a phospholipid
A
- modified triglycerides, contain phosphorus
-1 fatty acid chain is replaced with a phosphate group
12
Q
Features of phospholipids
A
- hydrophobic tail (non-polar)
- hydrophillic head (charged)
- form a bilayer
- surfactants= form a layer on the surface of water
13
Q
Biological roles of lipids (due to being non-polar)
A
- hormone production
- electrical insulation (synaptic transmission)
- waterproofing of surfaces
- membrane formations
14
Q
Other roles of lipids
A
- long-term energy storage
- thermal insulation
- cushioning/ protection
- buoyancy
15
Q
Structure and functions of sterols
A
- a type of lipid found in cells
- complex alcohol molecules
- based on a 4 carbon ring structure with a hydroxyl
group - have a hydrophillic hydroxyl group, the rest is hydrophobic
