According to Oswald Tippo classification blue green algae are member of:-

Options

A. Embryophyta
B. Thallophyta
C. Tracheophyta
D. Bryophyta

Answer

**Step-by-Step Solution:**

1. **Understand the Classification System**: Oswald Tippo proposed a classification system for the plant kingdom in 1942, which divides plants into two sub-kingdoms: Thalophyta and Embryophyta.

2. **Define Thalophyta**: Thalophyta includes plants that have a thalloid structure, meaning they do not have a differentiated body structure like roots, stems, or leaves. They also do not exhibit a distinct alternation of generations and lack embryos.

3. **Define Embryophyta**: In contrast, Embryophyta consists of plants that have a more complex structure with differentiated organs and show a regular alternation between the sporophyte and gametophyte generations. These plants also contain embryos.

4. **Identify the Classification of Blue-Green Algae**: Blue-green algae, also known as cyanobacteria, are simple, thalloid organisms that do not have a complex structure or embryos. Therefore, they fit the criteria for Thalophyta.

5. **Conclusion**: Based on Oswald Tippo's classification, blue-green algae are classified under Thalophyta.

**Final Answer**: Blue-green algae are members of **Thalophyta** (Option 2).

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