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

Options

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

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks for the term used to describe an undifferentiated mass of plant cells that is cultivated on a nutrient medium.

2. **Identifying the Process**: When plant cells are grown in a nutrient medium, they can proliferate and form a mass of cells that have not yet differentiated into specific cell types.

3. **Defining the Term**: The undifferentiated mass of plant cells that forms during this process is known as "callus."

4. **Analyzing the Options**:
- Option 1: Callus - This is the correct answer as it refers to the undifferentiated mass of cells.
- Option 2: Bud - This is incorrect because a bud is a structure that can develop into a flower or leaf, not an undifferentiated mass.
- Option 3: Clone - This is also incorrect as a clone refers to a genetically identical copy of a plant, not to an undifferentiated mass.
- Option 4: Skein - This is not relevant in this context, as it pertains to grafting and does not describe the mass of cells grown in a nutrient medium.

5. **Conclusion**: Therefore, the correct answer to the question is that the undifferentiated mass of plant cells grown on a nutrient medium is called "callus."

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