A thallus refers to plant body having

Options

A. Vascular system
B. Stem and leaves but no roots
C. Root and stem but no leaves
D. No distinction of stem, leaves and roots.

Answer

**Step-by-Step Solution:**

1. **Understanding the term "thallus":**
- A thallus refers to a type of plant body that is not differentiated into distinct organs such as stems, leaves, and roots.

2. **Identifying the characteristics of a thallus:**
- The thallus is typically composed of filaments or plates of cells.
- It can vary in size from unicellular structures to more complex forms that may resemble trees.

3. **Analyzing the options provided:**
- The options include:
a) Vascular system, stem, and leaves, but no roots.
b) Root and stem, but no leaves.
c) No distinction of stem, leaves, and roots.
- The first option suggests the presence of a vascular system, which is not characteristic of a thallus.
- The second option implies the presence of roots and stems, which contradicts the definition of a thallus.
- The third option correctly states that there is no distinction between stems, leaves, and roots.

4. **Conclusion:**
- The correct answer is that a thallus refers to a plant body having no distinction of stem, leaves, and roots.

**Final Answer:** A thallus refers to a plant body having no distinction of stem, leaves, and roots.

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