Whatever be the life span, death of every individual organism is a certainty, i.e., no individual is immortal, except

Options

A. Human beings
B. Amoeba and Paramoecium
C. Single-celled organisms
D. Both (2) and (3)

Answer

To solve the question about which organisms are considered immortal, we will analyze the options provided step by step.

### Step-by-Step Solution:

1. **Understanding the Question**: The question states that every individual organism has a certainty of death, except for certain organisms that are considered immortal. We need to identify these organisms from the given options.

2. **Analyzing the Options**:
- **Option 1: Human Beings**: Humans are mortal organisms with an average lifespan of around 70 years. Therefore, this option is incorrect as humans do die.

- **Option 2: Amoeba and Paramecium**: Both amoeba and paramecium are unicellular organisms. They reproduce asexually through a process called mitosis. When they divide, they do not die; instead, they create two new cells from one. This process allows them to continue existing in a form, which leads to the conclusion that they do not have a definitive lifespan like multicellular organisms. Thus, they can be considered immortal in the context of individual cells.

- **Option 3: Single-Celled Organisms**: This option is similar to option 2, as it refers to organisms like bacteria and protozoa, which also reproduce asexually and do not die in the traditional sense. They continue to exist through their reproductive processes.

- **Option 4: Both 2 and 3**: Since both amoeba and paramecium (option 2) and single-celled organisms (option 3) are immortal in the context of their reproduction, this option is correct.

3. **Conclusion**: The correct answer is option 4, which states that both amoeba and paramecium (option 2) and single-celled organisms (option 3) are considered immortal.

### Final Answer:
Both 2 and 3 (Amoeba and Paramecium, and Single-Celled Organisms) are considered immortal.

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