oxidative phosphorylation Flashcards
where does this occur
inner membrane of mitochondria
role of
making ATP by donating electrons to complees in membrane - comlexes being lipids/ protons
how does it begin
NADH and FADH wanting to donate their electrons
how do nadh and fadh enter mitochondria
via shuttles
what do electrons enter as if using the malate aspartate shuttle
NADH
what do electrons enter as if using the glycerol-3-phosphate shuttle
FADH2
what do fadh and nadh give their electrons to
complex I and complex II
complex I
flavin mononucleotide
comples II
succinate dehydrogenase
where do electrons from complexes I and II flow
directly to Coenzyme Q, which is also called ubiquinone
what does coenzyme q pass on the electrons to
to a series of cytochromes, which are proteins that contain heme groups.
cytochrome III - not important
made up of cytochrome b and cytochrome c1, and then electrons move over to cytochrome c, and from there the electrons get passed to complex IV, which is composed of cytochromes a and a3, which are together referred to as cytochrome oxidase
role of cytohcrome oxidase
transfers the electrons to the final electron acceptor, oxygen, making the oxygen electronegative enough to grab two protons - making a molecule of H20.
what happens if a cell doesnt recieve enough o2
electron transport chain gets interrupted and ATP synthesis doesn’t happen
what creates the electrical current
complexes rapidly passing electrons off to one another
role of electrical current
creates energy that drives complexes I, III, and IV to pump positively charged protons out of the mitochondria and into the space between the inner and outer mitochondrial membrane, creating a proton gradient across the inner mitochondrial membrane
what complexes span the inner mitochodnrial membrane
complexes I, III, and IV
is the gradient stable or unstable
considered unstable because the protons are always trying to equilibrate across the inner mitochondrial membrane, even though it’s totally impermeable to them
how do proteins get across the membrane
use a special proton channel called F0, that’s attached to an enzyme called F1
what does atp use to be pumped out of the mitochondria and into the cytoplasn
ATP/ADP anitporrt
how mnay atp does 1 nadh that donates its electrons make
3 as it activtes 3 proton pumps; I,III and IV
how many atp does fadh2 make
2 as it skips complex 1, and starts at complex 2, activating only 2 proton pumps - complexes III and IV
is ETC controlled hormonally
no
