Which is a wrong pair about `C_4` plants

Options

A. Mesophyll - Homogeneous
B. Chloroplasts - Dimorphism
C. PEP carboxylase - present in bundle sheath chloroplast
D. RUBISCO - present in abundance in Chloroplasts of bundle sheath cell

Answer

To solve the question regarding which pair about C4 plants is wrong, we will analyze the given options step by step.

### Step 1: Understand the Characteristics of C4 Plants
C4 plants have a unique photosynthetic pathway that allows them to efficiently fix carbon dioxide in hot and dry environments. They utilize a special leaf anatomy known as Kranz anatomy, which involves two types of cells: mesophyll cells and bundle sheath cells.

### Step 2: Identify the Key Components
1. **Mesophyll Cells**: These cells are responsible for the initial fixation of CO2 using the enzyme PEP carboxylase. They contain chloroplasts that are generally granule-lacking and starch-poor.

2. **Bundle Sheath Cells**: These cells surround the vascular bundles and are involved in the Calvin cycle. They contain a high number of chloroplasts that are starch-rich and granule-lacking.

3. **Chloroplast Dimorphism**: This refers to the difference in chloroplast structure and function between mesophyll and bundle sheath cells.

### Step 3: Analyze Each Pair
- **Mesophyll Cells - Homogeneous Chloroplast**: This is correct. Mesophyll cells have a uniform type of chloroplast.

- **Dimorphism**: This is also correct. C4 plants exhibit chloroplast dimorphism between mesophyll and bundle sheath cells.

- **PEP Carboxylase Present in Bundle Sheath Chloroplast**: This is incorrect. PEP carboxylase is present in mesophyll cells, not in bundle sheath cells.

- **Ribulose-1,5-bisphosphate Carboxylase (Rubisco) Present in Abundance in Chloroplast of Bundle Sheath Cells**: This is correct. Rubisco is abundant in bundle sheath cells, where the Calvin cycle occurs.

### Conclusion
The wrong pair about C4 plants is the one stating that "PEP carboxylase is present in bundle sheath chloroplast." This is incorrect because PEP carboxylase is found in mesophyll cells.

### Final Answer
The wrong pair about C4 plants is: **PEP carboxylase present in bundle sheath chloroplast.**