Define translocation.

Explanation

**Step-by-Step Text Solution:**

1. **Definition of Translocation**: Translocation is the process by which organic compounds, particularly the products of photosynthesis (known as photoassimilates), are transported from the source (where they are produced) to the sink (where they are utilized or stored) within a plant.

2. **Source of Photoassimilates**: The primary source of these organic compounds is the leaves of the plant, which are the main sites of photosynthesis. During photosynthesis, plants convert light energy into chemical energy, producing energy-rich carbon compounds such as sugars.

3. **Transport Mechanism**: The transport of these photoassimilates occurs through specialized vascular tissue called phloem. Phloem is responsible for the long-distance transport of nutrients and is essential for the distribution of sugars produced during photosynthesis.

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