Undifferentiated mass of plant cells grown on nutrient medium is called:

Options

A. callus
B. bud
C. clone
D. scion

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term that describes an undifferentiated mass of plant cells that are grown on a nutrient medium.

2. **Analyzing the Options**:
- **Option A: Callus** - This refers to an unorganized and unspecialized mass of cells derived from parenchymatous tissue, typically grown on a nutrient medium for research or propagation.
- **Option B: Bud** - A bud is an outgrowth from a plant, such as a flower bud, arising from meristematic tissue, and is not an undifferentiated mass.
- **Option C: Clone** - A clone is an organism that is genetically identical to another, produced through asexual reproduction, and does not refer to a mass of cells.
- **Option D: Scion** - A scion is a part of a plant that is cut and used in grafting, which does not represent an undifferentiated mass of cells.

3. **Identifying the Correct Answer**: Based on the definitions and characteristics of each option, the term that best fits the description of an undifferentiated mass of plant cells grown on a nutrient medium is **Callus**.

4. **Final Answer**: The answer to the question is **Callus**.

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