ABI 102, EXAM 4 QUESTIONS AND ANSWERS 100%
CORRECT!!
What are near equilibrium reactions Answers :Easily reversible
Rate controlled by concentration of substrate vs product
What are the characteristics of reactions that are far from equilibrium Answers :Rate of reaction is slow
Accumulation of reactant (enzyme is saturated)
Irreversible only changes in enzyme can alter rate
What is flux? Answers :Rate of flow of metabolites through a metabolic process
What is flux set by? Answers :Set by the rate determining step
How can flux be controlled? Answers :Allosteric control
Covalent modification (ie: phosphorylation)
Substrate cycle (enzyme determines direction depending on which direction is working faster)
Genetic control
What is the relationship between reduction potential and free energy? Answers :Positive reduction potential=negative free energy
Draw out/describe glycolysis Answers :
How is glycolysis regulated Answers :Mostly at PFK
ATP is allosteric inhibitor
ADP/AMP/fructose-2,6 bisphosphate is allosteric activator
What is the difference between the R state (active) and T state of PFK? Answers :R stat has Arg 162 to form ion pair with
T state has Glu 161 instead, reduced affinity for substrate
Describe substrate cycling in PFK Answers :Basically in resting muscle the forward/revers rxn will be running somewhat evenly so everything between F6P and FBP
How/when does Mannose enter glycolysis Answers :metabolized by hexokinase then an isomerase enters as F6P
How/when does fructose enter glycolysis Answers :Can only be broken down by hexokinase in muscle, but enters as F6P
Otherwise enters in as GAP (after step 4/5)
What can the metabolism of fructose also contribute to?
CORRECT!!
What are near equilibrium reactions Answers :Easily reversible
Rate controlled by concentration of substrate vs product
What are the characteristics of reactions that are far from equilibrium Answers :Rate of reaction is slow
Accumulation of reactant (enzyme is saturated)
Irreversible only changes in enzyme can alter rate
What is flux? Answers :Rate of flow of metabolites through a metabolic process
What is flux set by? Answers :Set by the rate determining step
How can flux be controlled? Answers :Allosteric control
Covalent modification (ie: phosphorylation)
Substrate cycle (enzyme determines direction depending on which direction is working faster)
Genetic control
What is the relationship between reduction potential and free energy? Answers :Positive reduction potential=negative free energy
Draw out/describe glycolysis Answers :
How is glycolysis regulated Answers :Mostly at PFK
ATP is allosteric inhibitor
ADP/AMP/fructose-2,6 bisphosphate is allosteric activator
What is the difference between the R state (active) and T state of PFK? Answers :R stat has Arg 162 to form ion pair with
T state has Glu 161 instead, reduced affinity for substrate
Describe substrate cycling in PFK Answers :Basically in resting muscle the forward/revers rxn will be running somewhat evenly so everything between F6P and FBP
How/when does Mannose enter glycolysis Answers :metabolized by hexokinase then an isomerase enters as F6P
How/when does fructose enter glycolysis Answers :Can only be broken down by hexokinase in muscle, but enters as F6P
Otherwise enters in as GAP (after step 4/5)
What can the metabolism of fructose also contribute to?
