Which of the following levels of structure encompasses all the other?

Options

A. Tissue
B. Cell
C. Organism
D. Organ or system

Answer

To determine which level of structure encompasses all the others, we need to analyze the hierarchy of biological organization. Here’s a step-by-step breakdown:

### Step 1: Understand the Levels of Biological Organization
The biological organization can be broken down into several levels:
1. **Cell** - The basic unit of life.
2. **Tissue** - A group of similar cells that perform a specific function.
3. **Organ** - A structure composed of different types of tissues working together.
4. **Organ System** - A group of organs that work together to perform complex functions.
5. **Organism** - The complete living entity that can function independently.

### Step 2: Identify the Smallest Unit
The smallest unit in this hierarchy is the **cell**. It is the fundamental building block of all living organisms and can perform life processes independently.

### Step 3: Build Up to Larger Structures
- **Cells** aggregate to form **tissues**.
- **Tissues** combine to create **organs**.
- **Organs** work together in **organ systems**.

### Step 4: Determine the Encompassing Level
The **organism** is the level that encompasses all the other levels. It includes all cells, tissues, organs, and organ systems working together to sustain life.

### Conclusion
Thus, the level of structure that encompasses all the others is the **organism**.

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