[15] Glycolysis and Gluconeogenesis Flashcards
What is glycolysis?
The metabolic pathway that converts glucose into pyruvate.
What is gluconeogenesis?
The metabolic pathway that generates glucose from non-carbohydrate sources.
Where does glycolysis occur in the cell?
In the cytoplasm.
Where does gluconeogenesis mainly occur in the cell?
In the liver and kidney.
How many steps are there in glycolysis?
Ten steps.
What is the net ATP gain in glycolysis?
Two ATP.
What are the two phases of glycolysis?
Energy investment phase, Energy payoff phase.
What happens in the energy investment phase of glycolysis?
Two ATP molecules are used to phosphorylate glucose.
What happens in the energy payoff phase of glycolysis?
Four ATP molecules are generated.
What is the key regulatory enzyme in glycolysis?
Phosphofructokinase-1 (PFK-1).
What is the primary purpose of gluconeogenesis?
To maintain blood glucose levels during fasting or intense exercise.
Which compounds can be used for gluconeogenesis?
Lactate, glycerol, amino acids.
What is the main regulatory enzyme in gluconeogenesis?
Fructose-1,6-bisphosphatase (FBPase-1).
What is the role of pyruvate in glycolysis and gluconeogenesis?
It is the end product of glycolysis and the starting compound of gluconeogenesis.
What is the Cori cycle?
The process of converting lactate, produced by muscle cells during anaerobic conditions, back into glucose in the liver.
What is the difference between glycolysis and gluconeogenesis?
Glycolysis breaks down glucose into pyruvate, generating ATP. Gluconeogenesis creates glucose using non-carbohydrate sources, requiring ATP.
What are the roles of NAD+ and NADH in glycolysis?
NAD+ is reduced to NADH, capturing some of the released energy during glycolysis.
What is the role of NADH in gluconeogenesis?
NADH is oxidized to NAD+ during gluconeogenesis, providing the necessary energy.
What happens to pyruvate after glycolysis under aerobic conditions?
It enters the mitochondria for the citric acid cycle (Krebs cycle).
What happens to pyruvate after glycolysis under anaerobic conditions?
It is converted into lactate in the cytoplasm.
