Update} Questions and Complete Solutions –
UCLA.
Hexokinase - correct answer Tissue location: all tissues
Function: prevents glucose from diffusing out of the cell and prepares glucose for
glycolysis
Characteristics: low Km to work at lower [glucose]; inhibited by G6P
Glucokinase - correct answer Tissue location: liver
Function: activates PFK for glycogen synthesis; inhibits gluconeogenesis
Characteristics: Km of 5 mM to work when [glucose] is high; facilitates clearing
glucose from the blood when [glucose] is too high
F-2,6-BP - correct answer Produced: dephosphorylated PFK2
Function: activates PFK; inhibits gluconeogenesis
Characteristics: phosphorylation state depends on glucose levels; high [glucose] leads
to dephosphorylated PFK2; low [glucose] leads to phosphorylated PFK2
PFK - correct answer Function: the main control point of glycolysis
Characteristics: is activated by [F-6-P] and [F-2,6-BP]; inhibited by ATP
GAPDH - correct answer Function: dephosphorylates GAP to produce the high energy
intermediate 1-3-BP; produces NADH
Pyruvate Kinase - correct answer Function: dephosphorylates phosphonenolate to
generate ATP; is the second committed step (very low G)
, CHEM 153A FINAL Exam {fall 2026/2026
Update} Questions and Complete Solutions –
UCLA.
Characteristics: inhibited by ATP, citrate, fatty acids, NADH; activated by ADP/AMP, F-
2,6,-BP, F-1,6-BP
* Is a second committed step to ensure beginning/end of glycolysis are running at
the same rate
Glycolysis balanced equation - correct answer Glucose + 2NAD+ + 2Pi + 2ADP -> 2
pyruvate + 2 ATP + 2 NADH + 2H+ + 2H2O
NADH - correct answer Function: energy-containing electron carrier that's used to
generate ATP
Characteristics: reoxidized by complex 1 in ETC (aerobic); reoxidized through lactate
dehydrogenase (anaerobic)
Gluconeogenesis - correct answer Method for producing glucose when absent of
glucose
Regulated by different irreversible enzymes outside of glycolysis; (pyruvate kinase,
PFK1, hexokinase are bypassed)
First step in glycogen production - correct answer Glucokinase is used as the first step
because Hexokinase is inhibited by its product. Glucokinase can function at high
[glucose].