12.3 oxidative phosphorylation

Question 1

oxidative phosphorylation

Answer 1

energy of electrons within hydrogen atoms(in NADH and FADH) is conserved in formation of ATP

Question 2

site of oxidative phosphorylation

Answer 2

mitochondria cristae

Question 3

adaptations of mitochondria for op

Answer 3

1. occur in great numbers in metabolically active cells
2. have densely packed cristae for greater SA of enzymes and proteins

Question 4

electron transfer chain

Answer 4

• hydrogen atoms from glycolysis and krebs cycle combine with NAD and FAD

-reduced NAD AND FAD donate electrons of hydrogens to the first molecule in ETC

-electrons pass along chain of electron transfer carrier molecules in series of oxidation-reduction reactions

-electrons release energy as the flow along chain, causing active transport of protons across inner mitochondrial membrane and inter membranal space

• H+ ions build in inter membranal space before diffusing back into mitochondrial matrix through ATP synthase channels(phosphorylates one ADP per H+ ion)

-at end of chain, electrons combine with H+ and O2(final electron acceptor) to form water

Question 5

ETC energy release

Answer 5

move down energy gradient, allowing energy to be released gradually and usefully

-greater energy released in single step, the more its released as heat and not useful purposes

Question 6

alternative respiratory substrates

Answer 6

lipids and proteins can be used
-doesn’t need to be converted to carb

Question 7

lipid respiration

Answer 7

hydrolysed to glycerol and fatty acids

glycerol phosphorylated to triose phosphate
-enters glycolysis pathway and krebs cycle

fatty acid broken into 2C to acetyl CoA

oxidation produces 2C and many H atoms
-lipids release more than double energy of same mass of carb

Question 8

protein respiration

Answer 8

protein hydrolysed to aminoa cids

amino group removed before entering respiration pathway at different points depending on C number