Which of the following are likely to be present in deep sea water?

Options

A. Blue-green algae
B. Saprophytic fungi
C. Archaebacteria
D. Eubacteria

Answer

To determine which organisms are likely to be present in deep sea water, let's analyze each option provided in the question step by step.

### Step-by-Step Solution:

1. **Blue-Green Algae**:
- Blue-green algae, also known as cyanobacteria, are photosynthetic organisms. They require sunlight for photosynthesis.
- **Conclusion**: Since deep sea water lacks sufficient sunlight due to its depth, blue-green algae cannot thrive there.

2. **Saprophytic Fungi**:
- Saprophytic fungi are decomposers that typically feed on dead organic matter found on land.
- **Conclusion**: These fungi are not adapted to live in aquatic environments, especially in deep sea water, so they are unlikely to be present.

3. **Archaebacteria**:
- Archaebacteria are a group of microorganisms that can survive in extreme environments, including deep sea hydrothermal vents.
- They are known for their ability to perform anaerobic respiration, which allows them to thrive in environments devoid of oxygen.
- **Conclusion**: Archaebacteria are indeed likely to be present in deep sea water.

4. **Eubacteria**:
- Eubacteria, or true bacteria, are a diverse group of bacteria that can be found in various environments, including soil, water, and even extreme conditions.
- While some eubacteria can be found in deep sea environments, they are not specifically adapted to the extreme conditions like archaebacteria.
- **Conclusion**: Eubacteria may be present, but they are not as specialized for deep sea conditions as archaebacteria.

### Final Answer:
The organisms likely to be present in deep sea water are **Archaebacteria**.

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