which is a mode of long distance transfer

Options

A. diffusion
B. cytoplasmic streaming
C. active transport.
D. translocation

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a mode of long-distance transport in plants. We need to evaluate the options provided: Diffusion, Cytoplasmic Streaming, Active Transport, and Translocation.

2. **Analyzing Each Option**:
- **Diffusion**: This is a passive transport mechanism where molecules move from an area of higher concentration to an area of lower concentration. It is primarily responsible for the movement of gases in plants but is not suitable for long-distance transport of substances like sugars.

- **Cytoplasmic Streaming**: Also known as protoplasmic streaming, this process involves the movement of the cytoplasm within a cell. While it facilitates the movement of materials within cells, it does not serve as a long-distance transport mechanism between different parts of the plant.

- **Active Transport**: This process involves the movement of substances against their concentration gradient, requiring energy. While it is essential for certain cellular functions, it is not typically used for long-distance transport across the plant.

- **Translocation**: This refers to the movement of substances, particularly sugars, from the source (where they are produced, like leaves) to the sink (where they are utilized, like roots). This process occurs through the phloem and is indeed a long-distance transport mechanism.

3. **Conclusion**: Based on the analysis, the correct answer is **Translocation**, as it is the mode of long-distance transport in plants, specifically for the movement of sugars through the phloem.

**Final Answer**: Translocation

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