Which is not a primary meristem?

Options

A. promeristem
B. Protoderm
C. Periblem
D. Ground tissue

Answer

To determine which is not a primary meristem, we need to understand the definitions and functions of primary meristems and how they relate to other plant tissues. Here’s a step-by-step breakdown of the solution:

### Step-by-Step Solution:

1. **Understanding Meristems**:
- Meristems are regions of undifferentiated cells in plants that have the ability to divide and contribute to growth. They are primarily responsible for primary growth, which increases the length of the plant.

2. **Types of Primary Meristems**:
- The main types of primary meristems include:
- **Apical Meristem**: Located at the tips of roots and shoots, responsible for the elongation of these structures.
- **Protoderm**: A primary meristem that develops into the epidermis (outer layer) of the plant.
- **Periblem**: A primary meristem that contributes to the formation of the cortex and endodermis.

3. **Identifying Non-Meristematic Tissues**:
- Ground tissue is a type of permanent tissue that is responsible for various functions such as storage and photosynthesis. Unlike meristems, ground tissue has lost its ability to divide.

4. **Conclusion**:
- Since ground tissue is a permanent tissue and does not have the capacity for division like primary meristems, it is not classified as a primary meristem. Therefore, the answer to the question "Which is not a primary meristem?" is **Ground Tissue**.

### Answer:
Ground Tissue is not a primary meristem.

---