3.5.2 respiration Flashcards
what is a phosphorylation reaction?
transfer of a phosphate group to make it more reactive
what is a decarboxylation reaction?
removal of CO2
outline aerobic respiration
uses oxygen
produces more ATP
glucose completely broken down
carbon dioxide and water produced
outline anaerobic respiration
without oxygen
produces less ATP
glucose partially broken down
lactic acid produced
what are the 4 stages of aerobic respiration?
glycolysis
link reaction
krebs cycle
oxidative phosphorylation
where does glycolysis take place?
the cytoplasm
what are the 2 stages in glycolysis?
phosphorylation
oxidation
outline phosphorylation in glycolysis
glucose is phosphorylated by adding 2 phosphates from 2 molecules of ATP this produces 2 molecules of TP and 2 ADP
outline oxidation in glycolysis
TP is oxidised forming 2 molecules of pyruvate
NAD is reduced forming 2NADH
4 ATP are produced
why must glycolysis take place in the cytoplasm?
because glucose cannot cross the outer mitochondrial membrane
it breaks down into pyruvate because this can cross the membrane
what are the products of glycolysis?
2 reduced NAD
2 pyruvate
2 ATP (net gain)
where does the reduced NAD produced in glycolysis go?
to oxidative phosphorylation
where does the pyruvate produced in glycolysis go?
actively transported into the mitochondrial matrix for use in the link reaction
where does the ATP produced in glycolysis go?
used for energy
how many C atoms are in pyruvate?
3 carbon atoms
outline what happens during the link reaction
pyruvate is decarboxylated ( carbon dioxide is removed)
NAD is reduced it collects hydrogen from pyruvate
pyruvate is converted into acetate
no ATP is produced
acetate combines with coenzyme A to form acetyl coenzyme A
where does the link reaction take place?
mitochondrial matrix
in an anaerobic respiration what is the only stage that happens?
glycolysis
what are the products of anaerobic respiration in plants and yeast?
carbon dioxide and ethanol
what are the products of anaerobic respiration in animals and bacteria?
lactic acid
how is anaerobic respiration able to continue?
production of lactic acid, CO2 and ethanol regenerate NAD
this means glycolysis can continue even when oxygen is in short supply
how many carbon atoms are in acetyl coenzyme A?
2 carbon atoms
what are the 2 types of reaction that occur in the link reaction?
oxidation
decarboxylation
what are the products of the link reaction?
2 acetyl coenzyme A
2 carbon dioxide
2 reduced NAD