After glycolysis, fate of glucose in mitochondrial matrix is

Options

A. Hydrolysis
B. Oxidative decarboxylation
C. Reduction
D. Oxidation.

Answer

**Step-by-Step Text Solution:**

1. **Understanding Glycolysis**: Glycolysis is the first step in the breakdown of glucose, occurring in the cytoplasm, where one molecule of glucose (6 carbons) is converted into two molecules of pyruvic acid (3 carbons each).

2. **End Product of Glycolysis**: The end product of glycolysis is pyruvic acid. This is crucial as it is the molecule that will enter the mitochondrial matrix for further processing.

3. **Transport to Mitochondrial Matrix**: After glycolysis, pyruvic acid is transported into the mitochondrial matrix, where it undergoes further transformations.

4. **Link Reaction**: Before entering the Krebs cycle, pyruvic acid undergoes a link reaction (also known as the pyruvate decarboxylation). This reaction occurs in the mitochondrial matrix.

5. **Conversion to Acetyl CoA**: During the link reaction, each molecule of pyruvic acid is converted into acetyl coenzyme A (acetyl CoA). This is a crucial step as acetyl CoA is the substrate for the Krebs cycle.

6. **Role of Pyruvate Dehydrogenase Complex**: The conversion of pyruvic acid to acetyl CoA is facilitated by an enzyme complex known as the pyruvate dehydrogenase complex.

7. **Oxidative Decarboxylation**: This conversion process is termed oxidative decarboxylation because it involves the removal of a carbon atom (in the form of carbon dioxide) and the oxidation of pyruvic acid. Therefore, hydrogen and carbon dioxide are released during this reaction.

8. **Final Conclusion**: Hence, after glycolysis, the fate of glucose in the mitochondrial matrix is oxidative decarboxylation, where pyruvic acid is transformed into acetyl CoA.