Glycolysis — Flashcards

Flashcard 61: The hallmark of what glycogen storage disease is a flat venous lactate curve with a rise in ammonia levels during exercise?_____

Answer: McArdle disease

Flashcard 62: Cori disease is associated with accumulation of _____-like structures in the cytosol

Answer: limit dextrin

Flashcard 63: Which steps (2) of glycolysis require ATP? _____

Answer: 1. Glucose → Glucose-6-phosphate (Hexokinase/Glucokinase) 2. Fructose-6-phosphate → Fructose-1,6-bisphosphate (PFK-1)

Flashcard 64: 3-phosphoglycerate is converted into _____ via the enzyme mutase

Answer: 2-phosphoglycerate

Flashcard 65: Is hexokinase activity inhibited by glucose-6-phosphate? _____

Answer: Yes

Flashcard 66: Which glycolysis enzyme deficiency is the second most common cause of hemolytic anemia? _____

Answer: Pyruvate kinase deficiency

Flashcard 67: Phosphofructokinase-2 (PFK-2) is activated by the hormone _____

Answer: Insulin

Extra: In the fed state, insulin leads to the dephosphorylation of the PFK-2/FBPase-2 bifunctional enzyme, which activates the PFK-2 domain. This increases Fructose-2,6-bisphosphate (F-2,6-BP) levels, which is the most potent allosteric activator of PFK-1 (the rate-limiting enzyme of glycolysis).

Flashcard 68: Which two steps of glycolysis produce ATP?

Answer: 1. 1,3-bisphosphoglycerate → 3-phosphoglycerate (catalyzed by phosphoglycerate kinase) 2. Phosphoenolpyruvate → pyruvate (catalyzed by pyruvate kinase)

Extra: These steps are examples of substrate-level phosphorylation. Although 4 ATP are produced in total during the payoff phase, the net gain of glycolysis is 2 ATP (because 2 ATP are consumed in the investment phase).

Flashcard 69: Where in the cell does glycolysis occur?_____

Answer: Cytoplasm

Flashcard 70: Pyruvate kinase deficiency presents with _____ levels of 2,3-BPG

Answer: increased