tylasoid is intrusion of a

Options

A. structure into parenchyma
B. parenchyma into strutre other than tracheary element.
C. parenchyma into tracheary element
D. annular ingrowth into a cell.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the nature of tylosoids and what structure they are an intrusion of.

2. **Identifying the Key Terms**: The key term here is "tylosoid," which is related to parenchyma cells and their interaction with other structures in plants.

3. **Defining Tylosoids**: Tylosoids are formed when parenchyma cells intrude into adjacent tissues. This intrusion does not occur into tracheary elements or vessels.

4. **Analyzing the Options**:
- **Option 1**: Parenchyma into structure other than tracheary elements.
- **Option 2**: Parenchyma into tracheary elements.
- **Option 3**: Annular growth into a cell.
- **Option 4**: This option is not relevant based on the definition of tylosoids.

5. **Selecting the Correct Option**: Based on the definition and the explanation provided, the correct option is that tylosoids are an intrusion of parenchyma into structures other than tracheary elements.

6. **Conclusion**: Therefore, the answer to the question is that tylosoids are an intrusion of parenchyma into structures other than tracheary elements.

**Final Answer**: Tylosoids are an intrusion of parenchyma into structures other than tracheary elements.

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