Who classified tissues for the first time? How many types of tissue system are known?

Explanation

### Step-by-Step Text Solution:

1. **Identify the Scientist**: The first step is to determine who classified tissues for the first time. This was done by Julius von Sachs, a German scientist, in the year 1875.

2. **Define Tissues**: Tissues are defined as groups of cells that work in a coordinated manner to perform specialized functions. This definition helps to understand the significance of tissue classification.

3. **Classification Basis**: Julius von Sachs classified tissues based on their position and morphology. This means he looked at where the tissues are located in the plant and their structural characteristics.

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