An unorganised mass of parenchymatous cells, produced in a culture is called__________________.

Answer

**Step-by-Step Solution:**

1. **Understanding Tissue Culture**: Tissue culture is a technique used to grow plant cells, tissues, or organs in a controlled environment, typically in a laboratory setting. It involves taking a part of the plant, known as the explant, which can be roots, leaves, or any other part.

2. **Identifying the Explant**: The explant is the specific part of the plant that is taken and cultured. This part is placed in a nutrient medium that contains all the necessary growth hormones, proteins, and vitamins needed for the plant cells to grow and develop.

3. **Formation of Callus**: During the tissue culture process, if the concentration of growth hormones is not optimal or if there are other issues, the cells may not grow in an organized manner. Instead, they proliferate in a disorganized fashion, leading to the formation of an unorganized mass of cells.

4. **Definition of Callus**: This unorganized mass of parenchymatous cells that arises from the disorganized proliferation of cells is known as a "callus." The callus is a crucial step in plant tissue culture and can eventually lead to the regeneration of a whole plant if conditions are favorable.

5. **Final Answer**: Therefore, the answer to the question is that an unorganized mass of parenchymatous cells produced in culture is called a **callus**.

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