Radioactive tracer studies with `.^(14)C` have shown that

Options

A. Phloem transports organic nutrients
B. Phloem transports inorganic nutrients
C. Xylem transports inorganic nutrients
D. Xylem transport organic nutrients.

Answer

To solve the question regarding radioactive tracer studies with \(^{14}C\), we will follow these steps:

### Step 1: Understand the Role of \(^{14}C\)
Radioactive carbon, specifically \(^{14}C\), is used as a tracer in studies to track the movement and incorporation of carbon in biological processes, particularly in photosynthesis.

**Hint:** Think about how radioactive isotopes can be used to trace biological pathways.

### Step 2: Identify the Process of Photosynthesis
During photosynthesis, plants convert carbon dioxide and water into glucose and oxygen using sunlight. The glucose produced is an organic compound that can be further transformed into other carbohydrates.

**Hint:** Recall the overall equation of photosynthesis and the products formed.

### Step 3: Recognize the Transport Mechanism
The organic nutrients, primarily in the form of sucrose, are transported through the plant via the phloem. In contrast, the xylem is responsible for transporting water and minerals.

**Hint:** Remember the functions of xylem and phloem in plant physiology.

### Step 4: Conclude the Findings from \(^{14}C\) Studies
The studies using \(^{14}C\) show that the carbon from carbon dioxide is incorporated into glucose during photosynthesis, and this glucose is then transported through the phloem. Therefore, the radioactive carbon can be traced through the plant's vascular system, confirming that phloem is responsible for the transport of organic nutrients.

**Hint:** Consider how the movement of carbon compounds through the plant can be tracked using radioactive isotopes.

### Final Answer
The radioactive tracer studies with \(^{14}C\) have shown that organic nutrients are transported by the phloem in plants.

**Correct Option:** Option number 1.