The type of compounds not formed in `C_3` plants is

Options

A. 2C compound
B. 5C compound
C. 3C compound
D. 6C compound

Answer

**Step-by-Step Solution:**

1. **Understanding C3 Plants and the Calvin Cycle**:
- C3 plants utilize the Calvin cycle for photosynthesis, where carbon dioxide (CO2) is fixed into organic compounds.
- The Calvin cycle consists of three main stages: fixation, reduction, and regeneration.

2. **Identifying the Compounds Formed**:
- During the fixation stage, CO2 is combined with ribulose bisphosphate (RuBP), a 5-carbon compound.
- This reaction produces 3-phosphoglyceric acid (3-PGA), which is a 3-carbon compound.
- In the reduction stage, 3-PGA is converted into glyceraldehyde 3-phosphate (G3P), another 3-carbon compound.
- The regeneration stage involves the regeneration of RuBP, which is a 5-carbon compound.
- Ultimately, glucose, a 6-carbon compound, is produced from the G3P molecules.

3. **Listing the Types of Compounds**:
- From the above stages, we can summarize the types of carbon compounds formed:
- 3-carbon compounds: 3-PGA and G3P.
- 5-carbon compound: RuBP.
- 6-carbon compound: Glucose.

4. **Identifying the Compound Not Formed**:
- The question asks for the type of compound that is **not** formed in C3 plants.
- Based on our analysis, we see that 2-carbon compounds are not produced during the Calvin cycle in C3 plants.

5. **Conclusion**:
- Therefore, the type of compound not formed in C3 plants is the **2-carbon compound**.

**Final Answer**: 2-carbon compound.

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