Here's a breakdown of the levels of organization in biology:

1. Atoms - The basic building blocks of matter

2. Molecules - Groups of two or more atoms held together by chemical bonds

3. Organelles - Specialized structures within cells that carry out specific functions

4. Cells - The basic unit of life, containing organelles

5. Tissues - Groups of similar cells that work together to perform a specific function

6. Organs - Structures made of different tissues that work together to perform a specific function

7. Organ Systems - Groups of organs that work together to perform a complex function

8. Organism - A complete living being made up of organ systems

So, while cells are the fundamental units of life, tissues are the next level of organization, where similar cells come together to form a functional unit.