Electron Transport Chain Flashcards
key metabolic functions that occur in the mitochondria
oxidative phosphorylation
TCA cycle
beta-oxidation of fatty acids
what is the function of the inner mitochondrial membrane
generates gradients of ions and compartmentalizes metabolites
what is the electron transport chain
series of proteins and organic molecules that create a series of redox reactions that capture energy in a proton gradient
what is the goal of the ETC
couple energy stored in electron acceptors to a protein gradient that drives ATP synthesis
which complex oxidises NADH
complex I
NADH dehydrogenase
which complex oxidises FADH2
complex II
succinate dehydrogenase
which complexes pump protons
complex I, III, and IV
what do complex I and II reduce
ubiquinone
what reduces ubiquinone
complex III
cytochrome C reductase
what does complex III reduce
cytochrome C
what oxidises cytochrome C
complex IV
cytochrome C oxidase
what does cytochrome C oxidase reduce
what does it produce
4 hydrogens and 2 oxygens
creates 2 H2O
where is the ETC
inner mitochondrial membrane
how does the NADH from glycolysis access the matrix to be used in the ETC
via malate:
the hydrogen is donated to form malate from oxaloacetate in the malate-aspartate shuttle
malate enters the mitochondria via transporter
malate oxidised back to oxaloacetate in the TCA cycle in the matrix producing NADH
how does the NADH from the TCA cycle access the matrix to be used in the ETC
its produced there
TCA occurs in the matrix
;)
what is the final acceptor of electrons in the ETC
water
what are the overall functions of the ETC
regenerate electron acceptors for glycolysis and TCA cycle (NAD and FAD)
generate a proton gradient with a higher concentration of H+ in the IMS
what is standard reduction potential
a measure of the ability to accept or donate electrons
why is oxygen the found at the end of the ETC
it has the highest (most +ve) standard reduction potential
most likely to accept electrons
why do we need to breath (in relation to ETC ofc not just “yOu’LL cHoKe”
to provide oxygen to act as the terminal electron acceptor allowing respiration
what are prosthetic groups
cofactors that bind tightly to proteins or enzymes
what prosthetic groups are involved in electron transport
1: flavin mononucleotides and ubiquinone
2: heme and ubiquinone
3: Fe-S clusters
4: Cu
[are the numbers the complexes or a list? research which complexes use which p groups]
what does it mean that the Fe in heme is hexahedrally coordinated
it has 6 bonds
what two things can happen to iron atoms when they enter the mitochondrial matrix
storage
used to make prosthetic groups
