amount of citrates in krebs cycle
6
5
4
how do you know its 6 5 4
4C oxalocaetate plus 2C actyl
1 C lost - isocitrate decarboxylated
1 C lost before succinate
how reduced FAD and NAD create electro chemical graident
pass electrons to ETC
high energy electrons provide energy to power proton pumps
on inner mitochondrial memrbane
pumps H+ into inter membrane space
two enzyme types involved in conversion of pyruvate to acetyl CoA
dehydrogenase
decarboxylase
suitable tissue for mithochondrial study
muscle
high numbers of mitochondria
what could be deduced if oxygen consumption was low with the pyruvate as substrate but high with a-ketyoglutrate as substrate
low with pyruvate
link reaction not working
dehydrogenase is not active
no reduced NAD for ETC
what could be deduced if there was build up of any one of the krebs cycle intermediates
enzymes catalysing conversion of mol to the next in the cycle not functional
why is there raised blood lactate level in patients with mitochondrial disease
Electron transport chain is not working
pyruvate levels build up
NADH converted to lactate
where does krebs cycle happen
mitochondiron in the matrix
how does decarboxylation work
diffuses out of mitochondria into blood
carried as hydrogen carbonate ions
breathed out
how is reduced NAD produced in Krebs Cycle
dehydrogenation
removal of hydrogen ions
five pairs of hydrogens
NAD to reduced NAD
what happens to reduced NAD under anaerobic conditions
pyruvate is used to form lactic acid
regen NAD
W
Z
labelling
W is outer mitochondrial membrane
Z is mitochondrial matrix
where is H+ conc highest
X
explain reasons for reduced NAD being required to maintain proton gradient
reduced NAD supplies protons
bring high energy electrons
electrons supply energy for proton pumping
chemicals P and Q (question 3)
ADP
ATP
where does ADP+pi happen
cytoplasm
pathway for production of triose phosphate in glycolysis
glucose phosphorylated by ATP
2 phosphorylations
6C split to 3C
explain biochemical reasons for carrying out the reaction despite the fact lactate is toxic
allows NAD to be convereted back to NAD
allows ATP production without oxygen
allows glycolysis to continue
sometimes occurs in muscle fibres when short burst of very rapid ATP production is needed
only glycolysis required
oxygen supply too slow
ne need for \\\etc
no need to build up proton gradient
no need to transport pyruvate to mitochondrion
question 4 - features in chomon in chemical features of NAD/ FAD
2 the same
1 diff
both has 5 carbon sugar
both have 2 phosphate groups
FAD only contains one sugar and NAD contains 2
position of high energy bond of ATP
bond between terminal phosphate groups on ATP
why is SLP refered to as simplest and oldest way to make ATP
does not involve ETC
does not need ATP syntgetase
Does not need oxygen or electro chem gradient
A B table on question 4
4
2
