| A | B |
| symbiosis | The relationship of organisms living closely together. |
| vivid | Bright and intense. |
| devitalize | to lower the physical energy. |
| biopsy | The removal of living tissue for study. |
| vivacious | Lively and spirited. |
| microbe | Tiny life form. |
| antibiotic | Substance used to destroy or stop growth of microorganisms. |
| viable | Able to live or develop under favorable conditions. |
| biosphere | The part of Earth and the atmosphere in which living things exist. |
| vitality | Physical or mental energy. |