Overview of Glycolysis Flashcards
What is another name for glycolysis?
Embden-Meyerhof pathway
What are the final products of glycolysis?
2 pyruvate + 2ATP + 2NADH + 2 H20 + 4 H+
How many enzymatic reactions are involved in glycolysis?
10
Where does glycolysis take place?
In the cytosol of the cell
What is the net reaction of glycolysis?
glucose + 2 NAD+ + 2ADP + 2 Pi»_space;» 2 pyruvate + 2 NADH + 2 ATP + 2 H20 + 4 H+
How many pyruvate molecules are generated from 1 molecule of glucose in glycolysis?
2
How many ATP molecules are generated in glycolysis?
2
What is the first step of glycolysis catalyzed by?
Hexokinase
What is the product of the first step of glycolysis?
Glucose-6-phosphate (G6P)
What does hexokinase do in the first step of glycolysis?
Transfers a high energy phosphoryl group from ATP to glucose
What is the energy cost of the first step of glycolysis?
1 ATP
How selective of an enzyme is hexokinase?
Relatively non-specific; will bind mannos, fructose, and galactose
What is the cofactor of hexokinase?
Mg2+
What inhibits hexokinase? What kind of inhibitor is it?
ATP; competitive inhibitor
What are the two major functions of glycolysis?
1) Generate ATP
2) Form molecules that are the precursors for amino acids and fatty acids.
What is the only fuel used by the brain under starvation conditions and the only fuel used by red blood cells at all?
Glucose
Into what two stages can glycolysis be broken into?
1) Three-step conversion of glucose into fructose 1, 6-bisphosphate (a compound that can readily be cleaved into phosphorylated 3-carbon units).
2) Generation of ATP through the oxidation of the 3-carbon units to pyruvate.
In which steps of glycolysis is ATP consumed (used)?
1) Conversion of glucose to glucose-6-phosphate (-1 ATP)
2) Conversion of fructose-6-phosphate to fructose 1,6 bisphosphate (-1 ATP)
In which steps of glycolysis is ATP produced (made)?
1) Conversion of 1,3-bisphosphoglycerate to 3-Phosphoglycerate (catalyzed by Phosphoglycerate kinase) (+2 ATP)
2) Conversion of phosphoenolpyruvate to pyruvate (+2 ATP)
What happens to the 2 NADH produced in glycolysis?
Shunted into the electron transport for ATP formation and regeneration of NAD+.
What happens to the pyruvate produced in glycolysis under aerobic conditions?
Is enters the TCA cycle for complete oxidation to CO2 and H20 and synthesis of more ATP
What happens to pyruvate under anaerobic conditions?
1) In muscle, pyruvate is converted to lactate to regenerate NAD+ through homolactic fermentation.
2) In yeast, pyruvate is converted to NAD+ and ethanol through alcoholic fermentation
