Cell-plate is formed of smaller units called .................

Explanation

**Step-by-Step Solution:**

1. **Understanding the Cell Plate**: The cell plate is a structure that forms during the process of cytokinesis in plant cells. It is crucial for the division of the cytoplasm and the formation of new cell walls between two daughter cells.

2. **Formation of the Cell Plate**: During cytokinesis, vesicles containing cell wall materials gather at the center of the dividing cell. These vesicles fuse to form the cell plate.

3. **Role of Phragmoplast**: The phragmoplast is a structure that helps in the formation of the cell plate. It is composed of microtubules and is essential for guiding the vesicles to the center of the cell where the cell plate is formed.

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