Lecture 7 and 8: Carbohydrate Metabolism (Glucose Catabolism)

Flashcards covering the key concepts of carbohydrate metabolism, particularly glycolysis and related pathways.

Glycolysis

The metabolic pathway that breaks down glucose to pyruvate, generating ATP.

Hexokinase (HK)

The enzyme that catalyzes the phosphorylation of glucose to glucose-6-phosphate in the first step of glycolysis.

Phosphofructokinase (PFK)

The rate-controlling enzyme of glycolysis that phosphorylates fructose-6-phosphate to fructose-1,6-bisphosphate.

Aldolase

The enzyme that splits fructose-1,6-bisphosphate into dihydroxyacetone phosphate (DHAP) and glyceraldehyde-3-phosphate (GAP).

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH)

The enzyme that converts GAP to 1,3-bisphosphoglycerate (1,3-BPG), producing NADH.

3-Phosphoglycerate (3PG)

An intermediate in glycolysis produced from 1,3-bisphosphoglycerate after transfer of a phosphate group.

Phosphoenolpyruvate (PEP)

A high-energy intermediate formed from 2-phosphoglycerate in glycolysis, leading to the production of pyruvate.

ATP

A molecule that carries energy within cells, produced during glycolysis.

NAD+

A coenzyme involved in redox reactions, essential for glycolysis and regeneration of NADH.

Fermentation

An anaerobic process that converts pyruvate into lactate or ethanol, regenerating NAD+.

Glycolytic pathway

The series of enzymatic reactions that convert glucose into pyruvate, releasing energy stored in ATP.

Energy investment phase

The first phase of glycolysis where energy (ATP) is consumed during the conversion of glucose to fructose-1,6-bisphosphate.

Energy recovery phase

The second phase of glycolysis where ATP is generated from ADP by substrate-level phosphorylation.

Galactose

A hexose sugar that can be metabolized through glycolysis after conversion to glucose-1-phosphate.

Pentose Phosphate Pathway

A metabolic pathway parallel to glycolysis that generates NADPH and ribose-5-phosphate for nucleotide synthesis.