Krebs Cycle or Citric Acid Cycle

KREBS CYCLE OR CITRIC ACID CYCLE

So far, oxygen has not been required; this is how some organisms operate when no oxygen is available and what happens in multicellular animals when there is a relative lack of oxygen. When oxygen Is available, the acetyl-CoA enters the Krebs cycle. When there is no oxygen, fermentation happens. The Krebs cycle (also called the tricarboxylic acid cycle or citric acid cycle), takes place in the mitochondria matrix of the cell. Figure 21 shows the reactions that take place in the Krebs cycle: