cell integrity Flashcards
what is substrate level phosphorylation?
when ATP or its equivalents are produced directly by kinase
where is the bulk of ATP produced?
oxidative phosphorylation in the inner mitochondrial membrane
what are cristae (mitochondria)
folds of the inner membrane increasing surface area
where does oxidative phosphorylation take place?
inner membrane of mitochondria
outline the reaction of NADH re-oxidation
NADH + H+ + 1/2O2 ——> NAD+ + H2O ΔG -223Kj/mol
outline the reaction of FADH2 re-oxidation
FADH2 + H+ + 1/2O2 ——> FAD + H2O ΔG -170Kj/mol
what does the electron transport chain consist of?
4 membrane proteins : complex I-IV
2 mobile electron carriers: co-enzyme Q and cytochrome C
other names for complex I
NADH-Q oxidoreductase or NADH dehydrogenase
other names for complex II
succinate-Q reductase or succinate dehydrogenase
other names for complex III
Q-cytochrome C oxidoreductase
other names for complex IV
cytochrome c oxidase
other name for co-enzyme Q
ubiquinone
which complexes do protons pass through?
I,III and IV
where else is complex II used?
Krebs cycle (succinate dehydrogenase)
where does FADH2 enter the electron transport chain?
complex II so skips a proton (one less proton and so less ATP produced than NADH)
define redox reactions
electron transfer reactions involving a reduced substrate(which donates electrons and becomes oxidised) and an oxidised substrate(which accepts electrons and becomes reduced)
what is a redox couple?
a substrate that can exist in both oxidised and reduced forms
what is a redox potential?
the ability of a redox couple to accept or donate electrons
what reference do standard redox potentials use?
hydrogen electrode
what does a negative E0 imply?
the redox couple has a tendency to donate electrons(more reducing power than hydrogen)
what does a positive E0 imply?
the redox couple has a tendency to accept electrons(more oxidising power than hydrogen)
what happens to the electrons as they are passed down the electron transport chain?
they lose energy
what type of enzyme is ATP synthase?
multimeric
what are the parts of ATP synthase?
membrane bound F0 and an F1 part which projects into the matrix space
