Plants like sugarcane show high productivity and high efficiency of ` CO_(2)` fixation, because of

Options

A. Absence of photorespiration
B. EMP pathway
C. Calvin cycle
D. TCA cycle

Answer

**Step-by-Step Solution:**

1. **Identify the Plant Type:**
- The question refers to sugarcane, which is a tropical plant known for its high productivity and efficiency in CO2 fixation.

2. **Understand the Photosynthesis Pathway:**
- Sugarcane utilizes the C4 pathway for photosynthesis. This pathway is characterized by the initial fixation of CO2 into a 4-carbon compound, typically oxaloacetate, which is then converted into malate or aspartate.

3. **Recognize the Importance of the C4 Pathway:**
- The C4 pathway allows sugarcane to efficiently fix CO2 even under conditions of high light intensity and temperature, which are typical in tropical climates.

4. **Evaluate the Options:**
- **Option 1: Absence of photorespiration** - This is a key factor because C4 plants like sugarcane minimize photorespiration, a wasteful process that occurs in C3 plants, leading to higher efficiency in CO2 fixation.
- **Option 2: EMP pathway** - This is incorrect as the EMP pathway (Embden-Meyerhof pathway) is related to glycolysis, not CO2 fixation.
- **Option 3: Kelvin cycle** - This refers to the C3 pathway, which is less efficient in CO2 fixation compared to the C4 pathway.
- **Option 4: TCA cycle** - This is also incorrect as it relates to cellular respiration, not photosynthesis.

5. **Conclusion:**
- The correct answer is **Option 1: Absence of photorespiration**, which contributes to the high productivity and efficiency of CO2 fixation in sugarcane.

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