The period of growth is generally divided into three phases namely

Answer

### Step-by-Step Text Solution:

1. **Understanding Plant Growth**:
- Plant growth can be defined as the irreversible increase in the number and size of cells, organelles, and any part of the whole organism.

2. **Identifying the Three Phases**:
- The period of growth in plants is generally divided into three distinct phases:
- **Meristematic Phase** (also known as the formative phase)
- **Elongation Phase**
- **Maturation Phase**

3. **Describing the Meristematic Phase**:
- The **Meristematic Phase** consists of actively dividing cells located at the root and shoot apices.
- These cells are rich in protoplasm and have large nuclei, which are essential for the process of cell division.

4. **Describing the Elongation Phase**:
- The **Elongation Phase** follows the meristematic phase and includes cells that are adjacent to the meristematic zone.
- In this phase, there is significant cell enlargement due to increased vacuolation and the deposition of new cell walls.

5. **Describing the Maturation Phase**:
- The **Maturation Phase** comes after the elongation phase, where the cells reach their maximum size.
- During this phase, cells undergo thickening and protoplasmic modifications, eventually differentiating into various types of simple or complex tissues to perform specific functions.

### Summary:
The three phases of plant growth are:
1. Meristematic Phase
2. Elongation Phase
3. Maturation Phase

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