A full mature plant body, undifferentiated into root, stem and leaf is called.

Options

A. thallus
B. coenocytic
C. hyphae
D. callus

Answer

To solve the question, "A full mature plant body, undifferentiated into root, stem and leaf is called," we can follow these steps:

### Step 1: Understand the Terminology
We need to identify the terms related to plant structure. The question specifies a "full mature plant body" that is "undifferentiated." This means we are looking for a term that describes a plant body that does not have specialized structures like roots, stems, and leaves.

### Step 2: Analyze the Options
Let's evaluate the options given in the question:
1. **Thallus**: This term refers to a plant body that is not differentiated into roots, stems, and leaves. It is commonly associated with algae and some lower plants.
2. **Cynocytic**: This term refers to a multinucleate stage, typically seen in certain types of cells, not specifically related to plant structure.
3. **Hypha**: This is a term used to describe the filamentous structure of fungi, not plants.
4. **Callus**: This refers to a mass of undifferentiated cells, often seen in tissue culture, but it is not a fully mature plant body.

### Step 3: Identify the Correct Answer
From the analysis, the term that best fits the description of a "full mature plant body, undifferentiated into root, stem, and leaf" is **Thallus**. This is because thallus represents a body plan that lacks the differentiation seen in higher plants.

### Conclusion
Thus, the correct answer to the question is:
**Thallus** (Option 1).

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