| A | B |
| Cell | collection of living matter enclosed by a barrier that separates the cell from its surroundings; basic unit of all forms of life. |
| Schleiden | concluded that all plants are made of cells. |
| Schwann | concluded that animals are also made of cells |
| Virchow | Where a cell exists |
| Cell theory | idea that all living things are composed of cells |
| cell membrane | thin |
| cell wall | strong layer around the cell membrane in plants |
| Nucleus | the center of the atom which contains the protons and neutrons; in cells |
| Cytoplasm | material inside the cell membrane-but not including the nucleus. |
| Prokaryote | single-celled microorganism that lacks a nucleus. |
| Eukaryote | organism whose cells contain nuclei. |
| Organelle | specialized structure that performs important cellular functions within a eukaryotic cell. |
| What three statements describe the cell theory? | all living things are composed of cells |
| What is the main characteristic that distinguishes eukaryotes from prokaryotes? | cells of eukaryotes have a nucleus |