Any part of a plant taken out and grown in a test tube, under sterile conditions in a special nutrient media that plant part is called

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about a specific term used for any part of a plant that is taken out and grown in a test tube under sterile conditions.

2. **Identifying the Technique**: The process described in the question is related to a scientific technique known as tissue culture. This technique involves growing plant cells or tissues in a controlled environment.

3. **Defining the Term**: In the context of tissue culture, the part of the plant that is taken for this process is referred to as an "explant."

4. **Types of Explants**: An explant can be any part of the plant, such as a leaf, bud, root, stem, or even a pollen grain in specific cases like haploid culture.

5. **Conclusion**: Therefore, the answer to the question is that the part of the plant taken out and grown in a test tube under sterile conditions in a special nutrient media is called an "explant."

**Final Answer**: Explant

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