Lecture 4-Role of Fat Flashcards
what dominated a adipocyte
lipid droplet
where are triglycerides stored within adipocytes
triglycerides are stored in lipid droplets within the cytoplasm of adipocytes
what are the other functions of adipocytes
maintains many other cellular functions
produce hormones
how is fat normally stored
triacylglycerol (3 fatty acids and a glycerol)
what can not cross the cell membrane, but fatty acids can
triacylglycerol can not cross cell membranes where as fatty acids can
what breaks down TAG (triacylglycerol)
lipoprotein lipase (LPL) enzyme
what is TAG (triacylglycerol) broken down into
free fatty acids, glycerol is disconnected
how are fatty acids carried in the blood
bound to albumin
what are tissues that lipoprotein lipase is found in
liver
adipocytes
muscle
lactating mammary glands
what are the two forms of lipoprotein lipase
hormone sensitive and hormone insensitive lipoprotein lipase
how are hormones that affect LPL are mediated through what
mediated through signalling pathways typically involving second messengers
what does hormone insenstive lipoprotein lipase provide and what does this mean in adipocytes
a base level of activity in the absence of hormones
adipocytes will continue to release a small amount of fatty acids in the absence of hormones
what will glucagon do to hormone sensitive lipase and what will this do
glucagon will stimulate hormone sensitive lipase
this will start breaking down TAG and release free fatty acids into the circulation
if insulin is present what will be inhibited in terms of fatty acids
inhibit the conversion of triacylglycerol to fatty acids
how is growth hormone different and what will it stimulate
growth hormone is a longer acting hormone (days to months)
it will stimulate the release fatty acids, providing fuels for metabolic activity
how is noradrenaline and adrenaline different to growth hormone and what does it do
much shorter acting, fight or flight
these will override the other settings, adipocytes will release fuel
Diacyl and monoacyl-glycerol have different what
different properties
TAG is broken down in several steps involving …
different enzymes
what are the two things that triacylglycerol is converted to before glycerol
diacylglycerol and monoacylglycerol