key term - TCA cycle

Definition

The TCA cycle, also known as the Citric Acid Cycle or Krebs Cycle, is a series of enzyme-catalyzed chemical reactions that are central to cellular respiration. It takes place in the mitochondria and is crucial for generating high-energy molecules like ATP, NADH, and FADH2 from acetyl-CoA derived from pyruvate oxidation.

5 Must Know Facts For Your Next Test

1. The TCA cycle occurs in the mitochondrial matrix.
2. It starts with the combination of acetyl-CoA and oxaloacetate to form citrate.
3. Each turn of the cycle produces 3 NADH, 1 FADH2, and 1 GTP (or ATP).
4. Carbon dioxide (CO2) is released as a byproduct during the cycle.
5. The cycle regenerates oxaloacetate, allowing it to continue processing acetyl-CoA.

Review Questions

Related terms

Glycolysis:

The process that breaks down glucose into pyruvate, producing ATP and NADH in the cytoplasm.

Electron Transport Chain: A series of protein complexes located in the inner mitochondrial membrane that use electrons from NADH and FADH2 to generate ATP.

Pyruvate Dehydrogenase Complex: An enzyme complex that converts pyruvate into acetyl-CoA before it enters the TCA cycle.