T1 - 3.1.3 lipids Flashcards
function of lipids
- energy source and store
- cell membranes
- insulation e.g. myelin sheath
- protection
- steroid hormones
structure of lipids
C, H, O
- less oxygen molecules than carbohydrates
- insoluble
- make up the monomers: fatty acids, glycerol
do lipids form polymers
NO
what are triglycerides made up of
3 fatty acids, 1 glycerides
characteristics of triglycerides
- tails are hydrophobic so therefore they are insoluble
- water cannot easily form H bond
why are triglycerides hydrophobic
the charges are evenly distributed
how do triglycerides form
condensation reactions creating an ester bond
what is a phospholipid made up of
characteristics of phospholipid head
hydrophilic as they are polar so can make H bonds
characteristics of phospholipid tail
hydrophobic as they are non- polar so cant make H bonds
what do phospholipids form together
CELL MEMBRANE - phospholipid bilayer
triglycerides vs. phospholipids
T - 3 fatty acids, no phosphate group, non-polar
P - 2 fatty acids, phosphate group, polar
unsaturated fat characteristics
- contain C=C bond
- low melting points so liquid at room temperature
- found in plant oils
- double bonds produce a definite kink in the carbon atom chain
saturated fat characteristics
- no C=C just C-C
- contain the maximum number of H atoms
- solid at room temperature as they have higher mtp
- found in animals
- strong intermolecular bonds between saturated triglycerides
cholesterol characteristics
- essential to good health
- vital component to cell membranes
- makes steroid sex hormones
- form bile salts involved in digestion/assimilation
- made in the liver from saturated fats
- needed in diet but only small amounts
