oxidative phosphorylation

what stage of aerobic respiration is this?

• the final stage

where does oxidative phosphorylation take place?

• the inner mitochondrial membrane

what is the process of oxidative phosphorylation?

• where energy carried by electrons, from reduced coenzymes (reduced NAD and reduced FAD), is used to make ATP

  • (the whole point of the previous stages is to make reduced NAD and reduced FAD for the final stage)

what 2 steps does oxidative phosphorylation require?

• the electron transport chain

• chemiosmosis

electron transport chain?

• NADH and FADH2 (from the krebs cycle) are oxidised by the first electron carrier in the inner mitochondrial membrane, regenerating NAD and FAD

• the hydrogen is split into hydrogen ions and electrons

protein gradient?

• the electrons pass along a series of electron carriers in the inner mitochondrial membrane, releasing energy as the electrons pass along

• this energy pumps the hydrogen ions from NADH and FADH2 from the mitochondrial matrix into the inter-membrane space

• this creates a protein gradient

chemiosmosis?

• the hydrogen ions diffuse back into the matrix through the ATP synthase enzyme

• as protons flow through the ATP synthase, energy is released

• this energy converts ADP and inorganic phosphate to ATP

the final electron acceptor?

• after the electrons have reached the end of the electron transport chain and hydrogen ions have flowed through the ATP synthase enzyme, oxygen accepts the electrons and combines with the hydrogen ions to form water

  • oxygen is called the final electron acceptor for this reason

what can ATP production be affected by?

• mitochondrial diseases

how do mitochondrial diseases affect the functioning of mitochondria?

• they can affect how proteins involved in oxidative phosphorylation or the krebs cycle function, reducing ATP production

• this may cause anaerobic respiration to increase, to try make up some of the ATP shortage

• this results in lots of lactate production, causing muscle fatigue and tiredness

• some lactate will also diffuse into the bloodstream, leading to high lactate concentrations in the blood

how much ATP can be made from one glucose molecule?

• 32