glycolysis and pentose phosph Flashcards
how many “priming” or “waterfall” steps are there in glycolysis
3
prep phase
step 1: hexokinase
adds phosphate to glucose by cleaving the super high energy beta-gamma phosphoanhydride bond within ATP
the beta gamma bond is so high energy in prep phase step 1 that what happens
there is unused free energy even after making the new phosphester bond , released as heat (explaining gibbs free energy)
is hexokinase step essentially irreversible
yes
T or F
according to le chaterliers principle, G6P never accumulates to a point that causes the reaction to go backwards
t
what does step 2 phosphohexose isomerase convert G6P to
Fructose -6-P
this step is governed by levels of substrate
whats the most important step in glycolysis?
Phosphofructokinase -1
what is the second waterfall step and first committed step for glycolysis
Phosphofructokinase -1
whats the fourth step
aldolase splitting the 6 carbon F1,6BP into two 3-carbon molecules, glyceraldehyde 3-
phosphate (GAP) and dihydroxyacetone phosphate (DHAP).
is aldolase reaction readily reversible in either direction
yes
what can be used for triacylglycerol synthesis (making fatty acids)
DHAP
step 5
triose phosphate isomerase
only what can proceed to step 6
GAP
step 6
Glyceraldehyde 3-Phosphate Dehydrogenase (GAPDH)
what does lactate dehydrogenase oxidize
NADH + H+ in anaerobic conditions