lipid metabolism Flashcards
how do lipids cross the cell membrane
through the fatty acyl carnitine shuttle
can FA be used for gluconeogenesis
no
where does beta oxidation occur
in the mitochondrial matrix
what are the products of one cycle of beta oxidation
1 acetyl Co A
1 FADH
1 NADH + H
1 fatty acyl CoA - shortened by 2 carbon atoms
what is the equation o the number of oxidation cycles for an even numbered saturated fat
(C/2) - 1
where and when are ketone bodies formed
in the liver mitochondria under fasting conditions
how are ketone bodies made
from acetyl Co A as a by product of beta oxidation
diffuse into the bloodstream
what do ketone bodies do in the brain
energy production and neurotransmitter synthesis
are ketone bodies toxic to peripheral tissues
no
what can ketone bodies lead to
ketoacidosis
what does glucose generate
acetyl Co A
what is acetyl Co A converted to
manonyl CO A
what is malonyl CO A
fatty acid synthesis precurose
what enzyme catalyses acetyl Co A to malonyl CoA
acetyl Co A carboxylase
what is Acetyl-CoA Carboxylase activity regulated by
nutrient and energy status
where are fatty acids made
cytoplasm
where are fatty acids degraded
matrix of mitochondria
what stimulate Acetyl-CoA carboxylase
citrate and insulin
what inhibit Acetyl-CoA carboxylase
AMP, glucagon, epinephrine palmitoyl Co A
how does citrate stimulate
allosterically
when is palmotoyl Co A abundant
when fatty acids in excess
what does epinephrine signal
requirement for energy
is fatty acid synthesis oxidative or reductive
reductive
what does fatty acid synthesis require
NADPH
what catalyses glycogen to glucose 1 phosphate
glycogen phosphorylase
what catalyses glucose 1 phosphate to glucose 6 phosphate
phosphoglucomutase
what does gluconeogenesis proceed via the syntehsis of
oxaloacetate
what is glycogenin
protein in centre of glycogen polymer - important as glycogen synthase can only ass glucose to existing glycogen chain
where are amino acids oxidised
TCA cycle
what are amino acids precursors for
gluconeogenesis
where does glycolysis occur
cytoplasm
what is the P/O ratio
a measure of the ATP molecules formed per O atom reduced
what has a more lower redox potential - NADH or FADH 2
FADH (less likely to donate electron)
what does a negative redox potential mean
lower affinity for electrons than H - more likely to donate
