18.4 Oxidative Phosphorylation Flashcards
(7 cards)
Where does oxidative phosphorylation take place
cristae
What is the process of oxidative phosphorylation
- The NADH and FADH donate the electrons of the hydrogen atoms to electron carrier proteins in the electron transport chain
- This releases the protons from the hydrogen atoms and these protons are pumped from the inner membrane space into the inter membrane space
- The electrons pass along a chain of electron carrier molecules in a series of redox reactions
- The electrons loose energy as they pass through the chain ans this is used to pump H+ across the cristae membrane
- the protons accumulate in the space between the two mitochondrial membranes before the diffuse into the matrix down their concentration gradient, through ATP synthase which combines ADP to produce ATP
- At the end of the chain electrons combine with these protons and oxygen to form water. The oxygen is the final electron acceptor
What is the theory of chemiosmosis
the energy in a chemical gradient established by electron movement us used to generate ATP
What is the evidence to support the chemiostomic theory
-the proton gradient across the inner membrane can be measured as it corresponds to a pH gradient
-isolated ATP synthase enzymes can produce ATP using a proton gradient even if no electron transport is occurring
-chemicals that block the electron transport chain inhibit the formation of a proton gradient and prevents ATP synthesis
What are the products of oxidative phosphorylation
34 ATP, H2O
Why is the ATP yield of respiration not always efficient
-some ATP is used up moving hydrogen from NADH made during glycolysis into the mitochondria
-some ATP is used moving pyruvate into mitochondria by active transport
-some energy is used to generate heat to maintain suitable body temperature for enzyme-controlled reactions
What is substrate level phosphorylation
the product on of ATP involving the transfer of a phosphate ground form a short lived, highly reactive intermediate
