Electron Transport Chain/Oxidative Phosphorylation Flashcards
what is oxidative phosphorylation?
Oxidative phosphorylation is made up of two closely connected components: the electron transport chain and chemiosmosis.
what happens in the electron transport chain?
electrons are passed from one molecule to another, and the resulting energy release is used to form an electrochemical gradient.
what happens in chemiosmosis?
energy stored in the gradient (made via electron transport chain) is used to make ATP.
HOw many electrons are transferred via oxidative phosphorylation?
2
what are the substrate and product of oxidative phosphorylation?
ubiquinone is converted to ubiquinol
How many H+ are ‘pumped up’/out of complex 1 a result of oxidative phosphorylation?
4
what is the role iron sulfur clusters in oxidative phosphorylation?
they carry/transfer a single electron at a time
IN COMPLEX ONE: what is the round and about way that electrons get transferred (seeing as iron sulfur clusters can only handle one electron at a time)?
2 electrons get transferred to FMN, then to FMNH2
THEN
1 electron adopts semi-panome (sp) form: FMNH
other electron ‘is sent through to complete the process’
IN COMPLEX THREE: what is the round and about way that electrons get transferred (seeing as iron sulfur clusters can only handle one electron at a time)?
ubiquinol gets converted back to ubiquinone, a series of signal electron transfers occur, 2 cytocrhome C molecules accept 1 electron each and go from oxidized form to reduced form
what is the long and short of cytochrome C?
it’s a recepter that has a 3+ iron bound in its heme ring and can only accept one electron at a time in order to switch from Fe 3+ to Fe 2+)
How many H+ are ‘pumped up’/out of complex 3 a result of oxidative phosphorylation?
4
where do the ‘pumped out’ H+ go?
into the intercellular space
IN COMPLEX THREE: what is the round and about way that electrons get transferred (seeing as iron sulfur clusters can only handle one electron at a time)?
Cytochrome C molecules drop off their 2 total electrons (and go back to oxidized state), the electrons interact with an oxegen molecule and 2 H+ to make H2O electron acceptor, and 2 more H+ get pumped out of the complex into the intercellular space
where do the complexes of oxidative phosphorylation exist?
in the membrane
what is the point of pumping out all these H+?
It creates a gradient that ‘spins a motor’ that powers ATP synthesis
not on the exam
