lecture 11: fatty acid syntghesis beta oxidation Flashcards
what is lipolysis
, triglycerides must first be broken down by hydrolysis into their two principal components, fatty acids and glycerol. This process, called lipolysis, takes place in the cytoplasm.
where does lipplysis occur
cytosol
what are the two hormones for regulation of lipolysis
glucagon
epinephrine
what is the effect of glucagon and epinephrine on the adipose tissie
increased trigylceride mobiliazition by activating the hormone sensitive lipase
what is the effect of epinephrine and glucagon on FA OXIDATION
it increases fatty acid tissues execpt the CNS and RBC
where is fatty acids built
cytosol
what is it called when you build a fatty acid
fatty acid synthesis
fatty acid biosynthesis
what is the trigger to start the build up of fatty acids (precursor)
acetyl coa
why is acetyl coa (where is it seen)
made from pyruvate and can go to the kreb cycle for energy
can go to form cholestterol
can be used to form fatty acids in the cytosol
can acetyl coa form fatty acids start in the mtiochondira
no , it needs to esceape the mtio and make the fatty acids i nthe cytsol of the cell
true or false: acetyl coa has a slight deviateion from tthe kreb cycle in order to form fatty acids
true
what is the first step acetyl coa must do in order to form a fatty acid
mustt merge with oxaloacetate to form citrate
will acetyl coa form citrate and aALWAYS leave the kreb cycle to form fatty acids
no
onyl when there is a need to form fatty acids
does actyle coa mix with oaxlo and form citrate in the mito or the cytsol
in the matrix
how deos citrate exit the mitochondira
needs a shuttle CITRATE SHUTTLE
TRue otr false; citrate can. exit the mitochondira easily (diffusion)
false it needs the citrate shuttle
what is the function of of the citrate shuttle
allows citrate to move past the mitochondria and into the cytosol
true or false: once citrate enters the cytsol, there is a reverese reaciton to turn it back into acetyl coa
true
why do we do the reverse reaction
there is no transporter to allow acetyl coa to go out of the memrbane
true or falseL acetyl coa is is hydrophillic and can easily pass through membvraen
false it is hydrophobic and needs a carrier to getit through the membrane
once citrate enters the cytsol, what reaction happens
citrate gets split back into acetyl coa and oxaloacetate (needs atp to get this reaction started)
does acetyl coa start as acetyl coa to form tvhe long chain fatty acyl coa
false it needs to get transformed into maloyn coa
what is the intiial fat compound made from actyl coa
malonyl coa (carbons in it that will add onto the malnyl group to because a long carbon fat chain)
WHat is the final profuct of fatty acid syhtesis
fatty acyl coa
can fatty acyl coa be immediately borken down
fatty acyl coa
what is the primer of fatty acid synthesis
acetyl coa
what is the purpose of malonyn
allows the addition of two carbons units
the two carbons that are added to the acetyl coa from malonyl must be reduced by what
for every 2 carbon unit, it must be reduced by 2 NADPH
what is the reaction for the syntehsis of palmiteic acid (c16)
Acetyl coa (2C) + 7 Malyn COa +14 NADPH + 14 H gives yyou
Palmmited acid (16 C) + 7 CO2 + 14 NADP + 8Coa + 6 h20
how does fatty acid synthesis work (general)
the maloyn coa (the backbone) will keep added carbons to the chain to form the proper length that it is programed to do
how many nadh is needed for every 2 carbons
2 nadph
becsides acetyl coa, what is needed in adequate concentrations for fatty acid syhtesis
carbohydate availability
why is it important to have adewuate carb availability
glucose goes to pyruvate which will ctreate the acertyl coa needed for fatty acid synthesis
what are the 3 important cycles coonnected to fatty acid sythesis
- glycolysis (need to make pyruvate)
- pyruvate oxidation to make acetyl coa
- kreb cycle to form the citrate
- pentose phosphate pathway to form the NADPH
where does the NADPH for fatty citrate come from
PPP
where does glucose/pyruvate for the fatty acid synthesis come from
glycolysis