All living things are made up of________

Explanation

**Step-by-Step Solution:**

1. **Understanding Living Things**: Begin by recognizing that all living organisms, whether plants, animals, or humans, share a fundamental building block.

2. **Identifying the Basic Unit**: The basic unit of life is the cell. Every living organism starts its life from a single cell known as a zygote.

3. **Cell Division and Growth**: As the zygote divides and grows, it forms many cells. These cells are the foundation for all living things.

4. **Formation of Tissues**: Groups of similar cells come together to form tissues. For example, muscle cells form muscle tissue.

5. **Development of Organs**: Different types of tissues combine to create organs. For instance, muscle tissue and nerve tissue together form the heart.

6. **Organ Systems**: Organs work together in systems, such as the circulatory system, to perform specific functions necessary for the organism's survival.

7. **Conclusion**: Therefore, all living things are fundamentally made up of cells, which are the smallest units of life.

**Final Answer**: All living things are made up of **cells**.

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