In which step of `C_(3)` cycle glucose is formed?

Options

A. Carboxylation, oxidation and reduction
B. Reduction
C. Regeneration
D. All of these

Answer

### Step-by-Step Solution:

1. **Understanding the C3 Cycle**: The C3 cycle, also known as the Calvin cycle, is a series of biochemical reactions that occur in the stroma of chloroplasts during the dark reactions of photosynthesis. This cycle is responsible for fixing carbon dioxide and synthesizing glucose.

2. **Identifying the Steps of the Calvin Cycle**: The Calvin cycle consists of three main stages:
- **Fixation**: Carbon dioxide is fixed by the enzyme RuBisCO, resulting in the formation of 3-phosphoglycerate (3-PGA).
- **Reduction**: In this stage, ATP and NADPH (produced in the light-dependent reactions) are used to convert 3-PGA into glyceraldehyde-3-phosphate (G3P).
- **Regeneration**: G3P is then used to regenerate ribulose bisphosphate (RuBP), allowing the cycle to continue.

3. **Formation of Glucose**: Glucose is formed during the reduction phase of the Calvin cycle. Specifically, G3P molecules are produced in this stage. For every six G3P molecules produced, one G3P molecule is used to form glucose, while the remaining five are recycled to regenerate RuBP.

4. **Conclusion**: Therefore, glucose is formed in the **reduction step** of the C3 cycle.