The process by which substances are transported over a long distance in plants through the vascular system is called :

Options

A. Transfusion
B. Translocation
C. Osmosis
D. Diffusion

Answer

To solve the question regarding the process by which substances are transported over long distances in plants through the vascular system, we can follow these steps:

### Step 1: Understand the Options
The question provides four options:
- A. Transfusion
- B. Translocation
- C. Osmosis
- D. Diffusion

### Step 2: Analyze Each Option
1. **Transfusion**: This term generally refers to the transfer of fluids, often in a medical context, and is not related to plant transport.

2. **Osmosis**: This is the movement of water across a semi-permeable membrane, primarily affecting water balance in cells, not long-distance transport.

3. **Diffusion**: This is the movement of molecules from an area of high concentration to an area of low concentration. It is effective over short distances but not suitable for long-distance transport in plants.

4. **Translocation**: This is the process by which substances (such as nutrients and water) are transported over long distances within the plant through the vascular system, specifically via xylem (for water and minerals) and phloem (for food).

### Step 3: Identify the Correct Answer
From the analysis, **translocation** is the only term that accurately describes the long-distance transport of substances in plants through the vascular system. Therefore, the correct answer is:

**B. Translocation**

### Step 4: Conclusion
The process by which substances are transported over a long distance in plants through the vascular system is called translocation.

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