2. Glycolysis and Gluconeogenesis Flashcards
what is the process on glycogenolysis
glycogen to glucose
What is glycolysis
glucose to pyruvate
what is glycogenesis
glucose to glycogen
what is gluconeogenesis. and where does this only happen?
pyruvate to glucose
only occurs in the liver and kidneys
what are the 2 forms of NAD+ and which type are they (OIL RIG)
NAD+ (oxidised)
NADH (reduced)
Glycolysis
- Generation of ATP
- Generation of reduced coenzymes which can be used to form ATP
- Generation of energy independent of oxygen-
- Breakdown of glucose to precursors for fat and protein synthesis (acetyl-CoA)
What is the role of hexokinase in glycolysis?
Glucose
to
Glucose-6-phosphate
by transferring phosphate from ATP
What is the role of Phosphoglucose Isomerase in glycolysis?
Glucose-6-phosphate
to
Fructose-6-phosphate
What is the role of phosphofructokinase in glycolysis?
Fructose-6-phosphate
to
Fructose-1,6-biphosphate by transferring a phosphate group from ATP
What is the role of Aldolase in glycolysis?
Fructose-1,6-disphospahte
to 2 carbon molecules. One is gyceraldehyde-3-phospahte and the other 3C molecule =
Dihydroxyacetone-phosphate
What is the role of Triose phosphate isomerase in glycolysis?
Converts dihydroxyacetone-phosphate into second molecule into glyceraldehyde-3-phosphate
What is the role of Glyeraldehyde-3-phosphate dehydrogenase in glycolysis?
glyceraldehyde-3-phospahte
to
1,3-biphosphoglyerate
through the molecules gaining a phosphate group and being oxidised. 2 NADH and 2 H+ are formed in the process
What is the role of phosphoglyeratekinase in glycolysis?
1,3-biphosphoglycerate
to
3-phosphoglycerate
the process transfers phosphates to ADP to form 2 molecules of ATP
What is the role of phosphoglyceratemutase in glycolysis?
3-phosphoglycerate
to
2-phosphoglycerate
What is the role of enolase in glycolysis?
2-phosphoglycerate
to
PEP (phosphoenolpyruvate)
What is the role of Pyruvate kinase in glycolysis?
PEP (phosphoenolpyruvate)
to
Pyruvate
it mediate the transfer of phosphates from PEP to ADP forming 2 ATP molecules
what are the 3 main sections of glycolysis and what is the main intermediates involved in each stage
- Preparation = glucose –> fructose-1,6 bisphosphate
- Splitting = fructose-1,6-bisphosphate –> 2 x 3 carbon compounds
- Harvest = 3C compounds –> pyruvate
At a slow metabolic rate NAD is not limiting. At a fast metabolic rate what happens?
NAD can become limiting. Here NADH is reversed back to NAD by creating lactate.
What is the main control enzyme of glycolysis and how?
PFK —> phosphofructokinase
It is inhibited by lots of ATP and stimulated by ADP
What are the steps of gluconeogenesis?
All the same steps of glycolysis but in reverse. stages 10, 3 and 1 are different however.
- Pyruvate to oxaloacetate via pyruvate carboxylase. then Oxaloacetate to phosphoenolpyruvate via PEP carboxykinase
- Fructose 1,6 bisphosphate to fructose 6 bisphosphate via fructose 1,6 bisphosphatase
- Glucose 6 phosphate to glucose via glucose 6 phosphotase
where does gluconeogenesis occur?
in the liver
