Exam 2 Regulation Flashcards
What inhibited hexokinase causing product inhibition?
glucose-6-phosphate
Glucagon is secreted when glucose is ________ in the blood
low
Insulin lowers or increases [glucose] in blood?
lowers
Is epinephrine an inhibitor or activator for insulin secretion?
inhibitor
Is glucose and inhibitor or activator of glucagon secretion?
inhibitor
What inhibits hexokinase?
G6P
What 2 things activate PFK-1?
AMP
F26BP
What activates fructose-2,6-bisphosphate?
insulin production
What 2 things inhibit F26BP?
ATP
glucagon/epi
What activates pyruvate kinase?
F-1,6-BP
phosphorylation of PK
AMP __stimulates/inhibits_______ PFK
ATP ___stimulates/inhibits_____ PFK
AMP: stimulates (signals that need more E produced)
ATP: inhibits (signals there is already enough E)
Glucagon and epinepherine stimulate the activation or degradation of F26BP?
degradation
Is PFK-1 inhibited or activated by ATP?
inhibited
Is G6PDH in PPP activated or inhibited by NADPH?
inhibited
Secretion of what hormone promotes glycogenesis?
insulin
When glucose is low what hormone is secreted?
glucagon
Glycogen phosphorylase is activated by _________ and inhibited by _______,_______,______ during glycogenolysis?
activated: AMP
inhibited: ATP, G6P, glucose
When there is a high demand for ATP glycogen phosphorylase is ____________
upregulated
When there is a high demand for ATP glycogen synthase is ____________
downregulated
Is glycogen phosphorylase activated by AMP?
yes
Is glycogen phosphorylase activated by ATP?
no
Is glycogen phosphorylase activated by glucose?
no
Is glycogen phosphorylase activated by G6P?
no
Is glycogen synthase activated by G6P?
yes
Is glycogen synthase activate when it phosphorylated or dephosphorylated?
dephosphorylated
Is glycogen phosphorylase activate when it phosphorylated or dephosphorylated?
phosphorylated
Is glycogen phosphorylated activated by epi/glucagon or insulin?
epi/glucagon
Is glycogen synthase activated by epi/glucagon or insulin?
insulin
Phosphorylation of glycogen phosphorylase ACTIVATES/INHIBITS glycogen breakdown
ACTIVATES
Phosphorylation of glycogen synthase ACTIVATES/INHIBITS glycogen synthesis
INHIBITS
What 2 things can stimulate glycogenesis in muscles?
low glycogen (from prior exercise)
insulin
Does AMP and Ca2+ stimulate or inhibit glycogenolysis?
stimulate
What stimulates glycogenesis in the liver?
insulin
What stimulates glycogenolysis in the liver?
epi/glucagon
Do muscles perform glycogenlysis when glucagon signals?
no (has no glucagon receptor)
Does glucagon/epi stimulate or inhibit gluconeogenesis?
stimulate
Does glycolysis or gluconeogenesis cost more energy?
gluconeogenesis
Does insulin stimulate or inhibit gluconeogenesis?
inhibit
____________ directly stimulates pyruvate carboxylase
acetyl coA
What are the 3 ways to regulate the CAC?
- NADH
- acetyl coA
- AMP
How does NADH regulate the CAC?
Inhibits PDH and other DHs (inihibits CAC)
How does acetyl coA regulate the CAC?
inhibits pyruvate DH (slows CAC)
activates pyruvate carboxylase (generates oxaloacetate=promotes CAC)
How does AMP regulate CAC?
stimulates PFK = increased glycolysis = increased CAC
In cells with minimal energy consumption (low need for ATP) , NADH ____inhibits/activates___ CAC?
inhibits (already plenty of E)
In cells with minimal energy consumption (low need for ATP) , is the flux of CAC high or low?
low
In cells with high energy consumption (high need for ATP) , is the flux of CAC high or low?
high (restore NADH)
How will a deficiency of Vitamin B1 affect the CAC?
decrease flux
How will a deficiency of Vitamin B1 affect PDH?
inhibits it