A. Tissue
B. Organ
C. Organ System D. Cell
E. Population F. Community G. Ecosystem H. Biosphere
2. A group of organs working together that perform major functions.
3. Group of similar cells that perform the same functions.
4. The basic unit of structure and functions in living things.
5. A body structure composed of different kinds of tissues that work together
6. Individuals of a species living in a specific area.
7. The sum of populations inhabiting a certain area.
8. The collection of all ecosystems, and it represents the zones of life on earth​