Which of the following region of root is responsible for the growth of the root in length ?

Options

A. Root cap
B. Region of meristematic activity
C. Region of elongation
D. Region of maturation.

Answer

To determine which region of the root is responsible for the growth of the root in length, we can analyze the different regions of the root:

1. **Root Cap**:
- The root cap is made up of calyptrogen cells.
- Its primary function is to protect the root tip from soil particles as the root grows through the soil.
- It does not contribute to the lengthening of the root.
- **Conclusion**: This option is incorrect.

2. **Region of Meristematic Activity**:
- This region contains meristematic cells that are actively dividing.
- While this region is important for growth, it primarily contributes to the formation of new cells rather than the elongation of existing cells.
- **Conclusion**: This option is also incorrect.

3. **Region of Elongation**:
- In this region, the cells do not increase in number; instead, they increase in size.
- The enlargement of these cells leads to the actual growth in length of the root.
- This is the primary region responsible for the elongation of the root.
- **Conclusion**: This option is correct.

4. **Region of Maturation**:
- In this region, cells undergo differentiation and become specialized for various functions.
- Root hairs are formed in this zone, which aids in absorption but does not contribute to the lengthening of the root.
- **Conclusion**: This option is incorrect.

**Final Answer**: The region of elongation is responsible for the growth of the root in length.

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