The Citric Acid Cycle (Krebs/TCA)

Flashcards covering key vocabulary and concepts related to the Citric Acid Cycle and its role in metabolism.

Citric Acid Cycle

A series of metabolic reactions that take place in the mitochondrial matrix, primarily involved in the oxidation of acetyl-CoA.

Acetyl CoA

A key substrate in the citric acid cycle derived from carbohydrates, fats, and proteins.

Pyruvate Dehydrogenase (PDH) Complex

A multi-enzyme complex that converts pyruvate into acetyl CoA, playing a critical role in linking glycolysis and the Krebs cycle.

Enzymatic Reactions

The series of specific reactions in the citric acid cycle that convert substrates through various metabolic processes, including enzyme-catalyzed steps.

Coh factors in PDH complex

Molecules that assist enzymes in catalyzing reactions, including NAD+, FAD, and Coenzyme A during pyruvate oxidation.

Intermediates of the Citric Acid Cycle

The compounds formed during the sequence of reactions within the cycle, including citrate, isocitrate, α-ketoglutarate, and oxaloacetate.

Regulatory Mechanisms

The controls that govern the activity of enzymes in the Krebs cycle, influenced by concentrations of ATP, NADH, and citrate.

NADH and FADH2

Reduced coenzymes produced during the Krebs cycle, critical for electron transport chain and ATP production.

Substrate-Level Phosphorylation

A process within the Krebs cycle that directly generates ATP through the transfer of a phosphate group.

Energy Production

The overall role of the Krebs cycle in generating energy-rich molecules, mainly NADH and FADH2, for ATP synthesis in oxidative phosphorylation.

Evolutionary Conservation

The phenomenon where the Krebs cycle is preserved across different organisms, underscoring its essential role in cellular metabolism.

Biological Roles of GTP

GTP functions similarly to ATP and is involved in protein synthesis and signaling pathways within the cell.