Study of internal structure of plants is called_____

Answer

The study of the internal structure of plants is called **plant anatomy**.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the term that describes the study of the internal structure of plants.

2. **Identifying the Correct Term**: The correct term for the study of the internal structure of plants is "plant anatomy."

3. **Alternative Term**: Another term that can be used interchangeably is "phytotomy."

4. **Historical Context**: Initially, the study of plant anatomy included both internal and external structures, which is known as plant morphology. However, since the mid-20th century, plant anatomy has been recognized as a separate field focusing specifically on internal structures.

5. **Current Focus**: Today, plant anatomy often involves investigations at the cellular level, including techniques such as sectioning of tissues and microscopy.

### Final Answer:
The study of internal structure of plants is called **plant anatomy** or **phytotomy**.

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