The central region of root apex containing less active cells is known as
(a) Plerome
(b) Dermatogen
(c) Periblem
(d) Quiescent zone

Options

A. Plerome
B. Dermatogen
C. Periblem
D. Quiescent zone

Answer

To solve the question regarding the central region of the root apex that contains less active cells, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the name of the central region of the root apex characterized by less active cells.

2. **Analyze the Options**:
- (a) Plerome: This refers to the central part of the root that gives rise to the vascular tissues.
- (b) Dermatogen: This is the outermost layer of the root apex that gives rise to the epidermis.
- (c) Periblem: This is the layer that develops into the cortex of the root.
- (d) Quiescent zone: This is a region in the root apex that contains less active cells and is known for its inactivity.

3. **Identify the Correct Answer**: The quiescent zone is specifically known for containing less active cells that divide infrequently. It is part of the root meristem and is characterized by its inactivity compared to other regions.

4. **Conclusion**: Based on the definitions and functions of the regions provided in the options, the correct answer is (d) Quiescent zone.

### Final Answer:
The central region of root apex containing less active cells is known as **(d) Quiescent zone**.

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