lipids Flashcards
what do lipids contain
carbon, hydrogen and oxygen
difference between lipids and carbohydrates
different proportions
in proportion to c and h, oxygen is much less
what type of molecule are lipids
non polar - cant dissolve in water
but can dissolve in organic solvents
how are triglycerides formed
combination of one glycerol mol and 3 fatty acids
ester bond formed as condensation reaction removes 3 molecules of water
what bond forms in triglycerides
ester
how many ester bonds are in triglycerides
3
saturation levels of triglycerides
monounsaturated
definition of hydrophilic
polar
molecule that can interact with water mol becase of it’s charge
definition of hydrophobic
non polar
molecule that cannot interact with water as it doesn’t have a charge
saturated definition
all carbon bonds are single
unsaturated definition
at least one carbon - carbon bond is not single
structure of a phospholipid
one of the 3 fatty acids are replaced by a phosphate group
what is the relevance of the phosphate group being polar
soluble in water
hydrophilic head
what do hydrophobic fatty acid tails produce
turn inwards and form a micell
what do a lot of phospholipids build up to be
a bilayer - basis of all cell membranes
triglyceride definition
three fatty acid molecules that are linked by condensation to a molecule of glycerol
ester bond definition
chemical bond formed as a result of condensation reaction between glycerol and fatty acids
properties of a saturated lipid
straight chain
molecules can align readily so are solid
useful for storage in molecules
properties of unsaturated lipids
one or more double bond
not straight
melt easier (oils)
what are monounsaturated lipids
only one double bond
what are polyunsaturated lipids
2 or more double bonds
triglyceride functions (4)
energy reserves
thermal insulation
protectin
producing metabolic water
waxes function
waterproofing
phospholipids functions (2)
structural
electrical insulation
3 differences in phospholipids / trigylcerides
number of fatty acid tails
phosphate group presence
polar / non polar
relevance of triglycerides being energy reserves
in both plants and animals
because lipids contain more carbon-hydrogen bonds than carbohydrates
relevance of triglycerides being thermal insulation
when stored under the skin lipids insulate against heat loss in the cold, or heat gain when hot
relevance of triglycerides function as protection
fat is often stored around delicate internal organs such as kidneys protecting against physical damage
relevance of triglycerides function as producing metabolic water
metabolic water is released from the body’s chemical reactions
triglycerides produce a lot when oxidised
relevance of phospholipids function as structural
in biological membranes
relevance of phospholipids function as electrical insulaters
surrounds the axons of nerve cells
effect of saturated fatty acids on human health
high saturation can lead to heart disease.
why are vegtebale oils liquid at room temp
has one or more double bond
animals have no double bond
what process joins fatty acid tails and the glycer mol
dehydration mol
