Red algae differs from green and brown algae in

Options

A. Absence of chlorophyll a
B. Undifferentiated cells
C. Not having any flagellate stage
D. All the above.

Answer

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

1. **Identify the Types of Algae:**
- Algae are classified into three main groups based on their pigment composition:
- Chlorophyceae (Green Algae)
- Pheophyceae (Brown Algae)
- Rhodophyceae (Red Algae)

2. **Examine the Pigments:**
- Each group of algae has different types of chlorophyll:
- Green algae (Chlorophyceae) contain chlorophyll A and B.
- Brown algae (Pheophyceae) contain chlorophyll A and C.
- Red algae (Rhodophyceae) contain chlorophyll A and D.

3. **Analyze the Options Given:**
- The options provided are:
1. Absence of chlorophyll A
2. Undifferentiated cells
3. Not having any flagellated stage
4. All of the above

4. **Evaluate Each Option:**
- **Option 1:** Absence of chlorophyll A is incorrect because all three types of algae possess chlorophyll A.
- **Option 2:** Undifferentiated cells is also incorrect as red algae have differentiated cells.
- **Option 3:** Not having any flagellated stage is correct because red algae do not have flagella, whereas green and brown algae do have flagellated stages in their life cycles.
- **Option 4:** All of the above is incorrect since not all previous options are true.

5. **Conclusion:**
- The correct answer is **Option 3: Not having any flagellated stage**. This is the key difference between red algae and both green and brown algae.

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