Flashcards in  Class 7: Glycolysis And Gluconeogenesis Deck (88)
Strategy to stage 1 glycolysis:
Traps the glucose in cell, for a A compound that can be readily cleaved into 2 phosphorylated 3- carbon units
What enzyme does liver use to convert glucose into glu-6-P?
What are the 2 steps involving energy investment in stage 1 glycolysis?
Glucose->G6P by hexokinase/glucokinase
F6P-> F1,6BP by phosphofructokinase
What regulates hexokinase?
Negative feedback inhibition by product- G6P
Regulation of glucokinase:
Stimulated by glucose, F-1P, and insulin
Inhibited by glucagon and F6P
Regulation of phosphofructokinase
Stimulated by AMP and F2,6-BP
Inhibited by ATP and Citrate
Which stage of glycolysis?
Fructose 1,6-BP into 2 3-C fragments by Aldolase reaction
Products are readily interconvertible
What conditions represent high energy? (3)
When there's high energy which of the products of stage 2, DHAP and GAP (G3P) is favored?
DHAP is favored under high energy conditions b/c it is converted to glycerol 3 phosphate- that way it can form triacylglycerols -FAT
What percentage of f1,6BP becomes GAP, usually?
Usually, 99% becomes GAP to continue glycolysis....in the event of high energy conditions the reaction will regress to DHAP for fat storage
Glyceraldehyde 3-P creates:
NADH (x2) that will be used in oxidative phosphorylation
1,3-BPG is converted to 3-PG by
Phosphoglycertae kinase and this forms the first ATP (x2) of glycolysis
2-PG is converted to_______ by:
Phosphoenolpyruvate by dehydration rxn by enolase
Phosphate is removed from phosphoenolpyruvate by:_________ creating:
Pyruvate is what type of molecular structure?
3 irreversible steps of glycolysis:
Regulation of pyruvate kinase:
Stimulated by insulin and Fructose 1,6-BP
Inhibited by Alanine, ATP, and glucagon
After glycolysis, aerobic:
Pyruvate to TCA;
Pyruvate to lactate--then, hopefully cori cycle...
Disaccharide of glucose and fructose makes=
Disaccharide composed of glucose and galactose =
Fructose and galactose are converted to:
In times of high energy, fructose quickly turns to:
Why would fructose quickly turn to fat in times of high energy?
Remember that GAP is readily interconvertible w/ DHAP, and although GAP is formed 99% of the time...this isn't the truth when there is high energy conditions b/c the GAP is converted to DHAP which becomes triacylglycerols- it is the backbone of fat.
3 regulated steps in glycolysis for ATP need
Main organ in glucose regulation
NO hexokinase in liver: it is glucokinase....how is this regulated?
Glucose is permanently trapped in liver cell.
It is not inhibited by G3P (product of glucokinase)
What type of regulation is used for pyruvate kinase:
Allosteric effectors and covalent modification
Pyruvate kinase is more ________ when phosphoirylated
Inactive- under conditions of low BG
Pyruvate kinase is more ________ when dephosphorylated
ACTIVE - under conditions of high BG