oxidative phosphorylation

• what is the ETC formed from?

  series of protein, bound in the inner mitochondrial membrane, cristae maximises the SA of the membrane increasing ATP production
• what happens in the first steps of the electron transport chain?

  1. electrons passed between the ETC proteins in series of redox reaction
  2. as they move down the chain, they lose energy, some of the energy is used to pump H+ ions from the matrix into the intermembrane space. remaining energy is lost as heat
• what is the 3rd and 4th steps in the ETC?

  3. inner mitochondrial membrane is impermeable to H+ ions, allowing a concentration gradient to form

  4. H+ ions move down the concentration gradient, into the matrix through the use of protein channels.
• what are the 5th and 6th step of the ETC

  • each H+ will be associated with ATP synthase which then phosphorylates one ADP for each H+ ion which passes through it
  • use of energy in a chemical gradient will generate ATP by flow of the H+ through ATP synthase. This is known as chemiosmosis
• what are the 7th and 8th steps of electron transport chain

  • final protein acceptor in ETC (cytochrome oxidase) donates electron pair to oxygen atom
  • final protein and electron acceptor as they bind with the H+ ions in matrix to form water
• what are the last steps in the electron transport chain

  • there is donation of electrons to the oxygen molecule, enough energy released to pump another H+ ion across the membrane
  • this can then be used to regenerate another molecule of ATP