Krebs Cycle and Energy Production

The Krebs cycle, also known as the Citric Acid Cycle or Tricarboxylic Acid Cycle, represents a crucial metabolic pathway in cellular energy production. The process begins with pyruvate transport and proceeds through multiple oxidation steps to generate energy-rich molecules.

Definition: The Krebs cycle is a series of chemical reactions used by all aerobic organisms to release stored energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins.

Vocabulary: Substrate-level phosphorylation refers to the direct transfer of a phosphate group from a substrate molecule to ADP, forming ATP.

Example: During the cycle, each pyruvate molecule produces 2 ATP, 6 NADH, and 2 FADH₂ through complete oxidation.

Highlight: The profit from one complete turn of the cycle includes 2 ATP, 6 NADH, 2 FADH₂, and 4 CO₂ molecules.

Quote: "Anytime molecule gets reduced, previous C gets oxidized."

The process involves several key steps:

1. Pyruvate transport into mitochondria
2. Conversion to Acetyl-CoA
3. Entry into the Krebs cycle
4. Multiple oxidation-reduction reactions
5. Generation of energy-carrying molecules