Glycolysis Flashcards
Define glycolysis.
Catabolism of glucose to yield two molecules of pyruvate.
Glucose + _______ + _______ + 2Pi
_______ + 2NADH + _______ + _______ + 2H+
Glucose + 2NAD+ + 2ADP + 2Pi
2 pyruvate + 2NADH + 2ATP + 2H2O + 2H+
Where does glycolysis take place?
In the cytosol.
How many reaction stages are there in glycolysis?
10.
What is reaction stage 1 and 2 known as?
Energy investment phase.
What is reaction stage 3 known as?
Energy harvesting phase.
What tissue does GLUT1 and GLUT3 diffuse across?
All mammalian tissues.
What tissue does GLUT2 diffuse across?
Liver and pancreatic cells.
What tissue does GLUT4 diffuse across?
Muscle and fat cells.
What tissue does GLUT5 diffuse across?
Small intestine.
In regards to glucose transport into cells, define isoform specificity.
Different affinities for glucose.
How many molecules of ATP are used in glycolysis?
Two.
State the three chemical reactions that take place in reaction stage 1 of glycolysis.
- Glucose —> Glucose-6-phosphate.
- Glucose-6-phosphate —> Fructose-6-phosphate.
- Fructose-6-phosphate —> Fructose-1,6-bisphosphate.
State the two chemical reactions that take place in reaction stage 2 of glycolysis.
- Fructose-1,6-bisphosphate —> Glyceraldehyde 3-phosphate + Dihydroxyacetone phosphate.
- Dihydroxyacetone phosphate —> Glyceraldehyde 3-phosphate.
Define preparatory phase.
Phosphorylation of glucose and its conversion to glyceraldehyde 3-phosphate.
What enzyme is used for the conversion of glucose to glucose-6-phosphate?
Glucokinase.
State the coupled reaction of glucose to glucose-6-phosphate.
Glucose + ATP —> Glucose-6-phosphate + ADP
State the process that occurs in reaction stage 1 of glycolysis.
There is a transfer of phosphoryl group from ATP to glucose. Hexokinase is used but requires Mg2+ ATP complex.
What complex does hexokinase require for essential kinase activity?
Mg2+ ATP complex.
What effect does glucose have upon hexokinase?
It induces a conformational change in hexokinase by placing ATP close to group C6 in glucose and excludes water from the active site.