Unicellular organism are capable of

Options

A. Independent existence
B. performing the essential function of life
C. well organized organ system
D. both (a) and (b)

Answer

To solve the question regarding the capabilities of unicellular organisms, we can break it down step by step:

### Step-by-Step Solution:

1. **Understanding Unicellular Organisms**:
- Unicellular organisms are those that consist of a single cell. Examples include amoeba and paramecium.

2. **Independent Existence**:
- Since unicellular organisms are made up of only one cell, they can live independently without relying on other organisms. This means they can carry out all necessary life processes on their own.

3. **Essential Functions of Life**:
- Unicellular organisms perform essential life functions such as:
- **Respiration**: They can exchange gases through diffusion.
- **Nutrition**: They can intake food and utilize it for energy.
- **Excretion**: They can remove waste materials from their body.
- **Reproduction**: They can reproduce asexually, often through processes like binary fission.

4. **Well-Organized Organ System**:
- Unicellular organisms do not possess a well-organized organ system. They lack specialized tissues and organs because they function as a single cell. In multicellular organisms, cells form tissues, tissues form organs, and organs form organ systems, which is not the case for unicellular organisms.

5. **Analyzing the Options**:
- a. Independent existence: True
- b. Performing the essential functions of life: True
- c. Well-organized organ system: False
- d. Both a and b: True

6. **Conclusion**:
- Since unicellular organisms can exist independently and perform essential life functions but do not have a well-organized organ system, the correct answer is option D: both A and B.

### Final Answer:
**D. Both A and B**

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