The Preparatory Stage
The preparatory stage, also known as the link reaction, is right before the actual Krebs Cycle.
Steps:
1. The two pyruvates from the glucose molecule are transported to the mitochondria (Before the Citric Acid Cycle).
- One pyruvate has 3 carbons
- There are 2 pyruvates in every glucose molecule
2. One Co-enzyme A (CoA) joins with the 3 carbon compound.
3. Then, pyruvate oxidation occurs. It is when one of the 3 carbons splits off the pyruvate, resulting in a 2 carbon compound, Acetyl-CoA (Khan Academy).
- The carbon that splits off is released as CO2.
4. NAD+ is reduced to NADH, which will go into the next few processes to produce ATP (Khan Academy).
5. The Acetyl-CoA enters the Krebs Cycle.
*This process occurs for both pyruvates.
*Adding oxygen to the link reaction, or pyruvate oxidation, allows the aerobic respiration process to continue. If no oxygen comes in link reaction, fermentation occurs.
Made by Lucia Brinzan