Red algae are similar to blue-green algae in possession of

Options

A. similar reserve food
B. nucleus
C. phycobilins
D. gas-vascuoles

Answer

To solve the question regarding the similarities between red algae and blue-green algae, we will analyze the characteristics of both types of algae based on the options provided.

### Step-by-Step Solution:

1. **Identify the Types of Algae**:
- Red algae belong to the class Rhodophyceae and are eukaryotic organisms.
- Blue-green algae, also known as cyanobacteria, are prokaryotic organisms.

2. **Examine the Options**:
- **Option 1: Similar Reserve Food**:
- Red algae store food as Floridian starch.
- Blue-green algae store food as regular starch.
- **Conclusion**: This option is incorrect as the reserve food forms are different.

3. **Option 2: Nucleus**:
- Red algae, being eukaryotic, have a nucleus.
- Blue-green algae, being prokaryotic, do not have a nucleus.
- **Conclusion**: This option is incorrect since they differ in nucleus presence.

4. **Option 3: Phycobilins**:
- Phycobilins are pigments found in both red algae and blue-green algae.
- Red algae contain phycoerythrin (which gives them a red color).
- Blue-green algae contain phycocyanin (which gives them a blue or greenish color).
- **Conclusion**: This option is correct as both types of algae possess phycobilins.

5. **Option 4: Gas Vacuoles**:
- Gas vacuoles are present in blue-green algae (cyanobacteria).
- Red algae do not have gas vacuoles.
- **Conclusion**: This option is incorrect since red algae lack gas vacuoles.

### Final Answer:
Red algae are similar to blue-green algae in possession of **phycobilins**.