Carbohydrate Metabolism

Front 1

3 enzymes that catalyze irreversible steps in glycolysis

Back 1

Hexokinase
Phosphofructokinase
pyruvate kinase

Front 2

rxn that produces NADPH in glycolysis

(need NAD+ to go back to NADH, otherwise glycolysis will stop)

Back 2

glyceraldehyde 3-phosphate dehydrogenase--> G3p oxidatively phosphorylated to 1,3 BPG

Front 3

Phosphofructokinase

Back 3

catalyzes committed step in glycolysis

key regulatory enzyme of glycolysis

Front 4

Two rxns that produce ATP in glycolysis via substrate level phosphorylation

Back 4

phosphoglycerate kinase --2 ATP formed

pyruvate kinase--2 ATPs produced

Front 5

Gluconeogenesis

Back 5

uses 2 enzymes: pyruvate carboxylase and PEP carboxylase to reverse actions of pyruvate kinase

(makes pyruvate go back to become glucose again)

Front 6

2 reactions of PPP that produce NADPH

Back 6

Glucose 6-phosphate dehydrogenase (oxidation rxn that produces lactone)

6-phosphogluconate dehydrogenase (produces ribulose 5-phosphate)

Front 7

explain why X-linked deficiency of glucose 6-phosphate dehydrogenase can cause severe hemolytic anemia

Back 7

NADPH needed to keep reduced form of glutathione in red blood cell

If not reduced, glutathione causes red blood cells to burst, causing anemia

Front 8

Gluconeogenesis: major precursors

Back 8

lactate, amino acids, and glycerol

Front 9

Key rxns in gluconeogenes: allow it to "by-pass" the irreversible steps in glycolysis

Back 9

by pass enzymes:

pyruvate carboxylase
phosphoenolpyruvate carboxykinase (PEP)
Fructose 1,6 bisphosphatase
glucose 6-phosphatase

Front 10

Malate shuttle

Back 10

oxaloacetate is transported to cytoplasm via this shuttle and it is the product of pyruvate carboxylase

Front 11

Cori cycle

Back 11

Lactate prod in skeletal muscle and RBC can be converted back to pyruvate in liver

pyruvate can enter gluconeogenic pathway and regenerate glucose

No net synthesis of glucose, bc lactate was prod from oxidation of glucose to begin with, but this removes toxic substance from muscle and blood

Front 12

Major precursor in de novo formation of glucose in liver

Back 12

Alanine

Front 13

Glucose 6-phosphatase

Back 13

the enzyme that breaks down glucose 6-phosphate into glucose and phosphate

Front 14

Glycogen synthesis

Back 14

UDP-glucose = "activated glucose"

Front 15

two key enzymes in regulation of glycogen metabolism

Back 15

glycogen phosphorylase and glycogen synthase