During glycolysis in cytoplasm, the decarboxylation reactions

Options

A. are not observed
B. occurs twice
C. occurs once
D. occurs in all the ten steps

Answer

### Step-by-Step Solution:

1. **Understanding Glycolysis**: Glycolysis is a metabolic pathway that converts glucose into pyruvate, producing ATP and NADH in the process. It occurs in the cytoplasm and consists of ten enzymatic steps.

2. **Identifying Decarboxylation Reactions**: Decarboxylation reactions involve the removal of a carboxyl group from a molecule, resulting in the release of carbon dioxide (CO2).

3. **Analyzing Each Step of Glycolysis**:
- The glycolytic pathway begins with glucose and ends with pyruvate.
- The steps include the conversion of glucose to glucose-6-phosphate, fructose-6-phosphate, fructose-1,6-bisphosphate, and so on, until pyruvate is formed.
- Throughout these steps, no carboxyl group is removed, and thus, no CO2 is released.

4. **Conclusion**: Since there are no steps in glycolysis where decarboxylation occurs (i.e., no CO2 is released), the correct answer to the question is that decarboxylation reactions are not observed during glycolysis.

### Final Answer:
**Decarboxylation reactions are not observed during glycolysis.**

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