The plant in which root, stem and leaves are undifferentiated is called

Options

A. Thallus
B. Flower
C. Parthenocarpy
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a type of plant where the root, stem, and leaves are not distinctly differentiated. This means that these parts do not have clear separations or specialized structures.

2. **Identifying the Plant Type**: The term that describes plants with undifferentiated structures is "Thallus". Thallus refers to the main body of certain types of plants, particularly algae, where there is no clear distinction between roots, stems, and leaves.

3. **Examples of Thallus**: Algae are a primary example of plants that have a thallus structure. In algae, the entire plant body is referred to as thallus, and it performs photosynthesis without having separate root, stem, or leaf structures.

4. **Classification**: Thallus plants belong to a group known as "Cryptogams". Cryptogams are primitive plants that do not have visible sex organs and include other categories such as bryophytes (mosses and liverworts) and pteridophytes (ferns).

5. **Conclusion**: Therefore, the answer to the question is that the plant in which root, stem, and leaves are undifferentiated is called "Thallus".

**Final Answer**: Thallus

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