What do we call the piece of DNA that is delivered by Agrobacterium tumifaciens that transforms normal cells into tumors?

Explanation

To answer the question, "What do we call the piece of DNA that is delivered by Agrobacterium tumefaciens that transforms normal cells into tumors?" we can follow these steps:

### Step-by-Step Solution:

1. **Understand Agrobacterium tumefaciens**: This is a bacterium that is known for its ability to transfer DNA to plant cells, particularly in dicotyledonous plants. It plays a significant role in plant pathology.

2. **Identify the Process of Infection**: When Agrobacterium tumefaciens infects a plant, it introduces a specific piece of DNA into the plant cells. This process is crucial for the transformation of normal plant cells.

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