In the `C_4` cycle, the 4 carbon - containing acids are formed in

Options

A. Mesophyll cells of maize leaf.
B. Mesophyll cells of cactus leaf.
C. Mesophyll cells of tomato leaf.
D. Mesophyll cells of banana leaf.

Answer

To solve the question about where the four-carbon containing acids are formed in the C4 cycle, we can follow these steps:

### Step 1: Understand the C4 Cycle
The C4 cycle, also known as the Hatch-Slack pathway, is a photosynthetic process that occurs in certain plants, known as C4 plants. In this cycle, carbon dioxide is fixed into a four-carbon compound.

### Step 2: Identify the Key Components
In the C4 cycle, the primary acceptor of carbon dioxide is a three-carbon molecule called phosphoenolpyruvate (PEP). When CO2 is fixed by PEP, it forms a four-carbon compound, which is typically oxaloacetate.

### Step 3: Determine the Location of Acid Formation
The four-carbon acids are specifically formed in the mesophyll cells of C4 plants. These mesophyll cells are responsible for the initial fixation of carbon dioxide.

### Step 4: Transport of Four-Carbon Acids
Once the four-carbon acids are formed in the mesophyll cells, they are then transported to the bundle sheath cells, where they undergo further processing to eventually release CO2 for the Calvin cycle.

### Step 5: Identify the Correct Answer
Given the options provided in the question, the correct answer is that the four-carbon acids are formed in the mesophyll cells of C4 plants, such as maize.

### Final Answer
The four-carbon containing acids in the C4 cycle are formed in the mesophyll cells of maize leaf.

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