the basic similarity among all the living organisms is that they are made up of

Options

A. tissues
B. organs
C. cells
D. organ systems

Answer

**Step-by-Step Solution:**

1. **Identify the Basic Similarity**: The question asks about the basic similarity among all living organisms.

2. **Understanding Living Organisms**: All living organisms, regardless of their complexity, share a fundamental characteristic.

3. **Cells as the Basic Unit of Life**: The smallest unit of life is the cell. Every living organism is composed of at least one cell. This is a critical point because it highlights that cells are the building blocks of life.

4. **Types of Organisms**: Organisms can be classified into two main categories:
- **Prokaryotes**: These are simple, unicellular organisms that do not have a nucleus (e.g., bacteria).
- **Eukaryotes**: These are more complex organisms that can be unicellular or multicellular and have a defined nucleus (e.g., plants, animals, fungi).

5. **Cell Functions**: Cells perform all necessary life processes such as digestion, respiration, and excretion. This emphasizes the importance of cells in maintaining life.

6. **Tissues, Organs, and Organ Systems**: Cells group together to form tissues, which then form organs, and finally, these organs work together in organ systems. However, the fundamental similarity remains that all these structures are ultimately made up of cells.

7. **Conclusion**: Therefore, the basic similarity among all living organisms is that they are all made up of cells.

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