Permanent tissues which are made up of more than one type of cells and these cells work together as a unit are known as ___________.

Answer

To solve the question regarding permanent tissues in plants, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Permanent Tissues**: Permanent tissues in plants are those that have differentiated and are no longer capable of division. They are responsible for various functions in the plant.

2. **Types of Permanent Tissues**: There are two main types of permanent tissues:
- **Simple Tissues**: These are composed of only one type of cell. Examples include parenchyma, collenchyma, and sclerenchyma.
- **Complex Tissues**: These are made up of more than one type of cell that work together as a unit.

3. **Identifying the Correct Type**: The question specifically asks for permanent tissues that consist of more than one type of cell. This description fits the definition of complex tissues.

4. **Examples of Complex Tissues**: The two primary examples of complex tissues in plants are:
- **Xylem**: Responsible for water transport.
- **Phloem**: Responsible for the transport of nutrients and food.

5. **Conclusion**: Based on the definitions and examples discussed, the answer to the question is that permanent tissues made up of more than one type of cell that work together as a unit are known as **complex tissues**.

### Final Answer:
Permanent tissues which are made up of more than one type of cells and these cells work together as a unit are known as **complex tissues**.

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