| A | B |
| classification | The grouping of objects or information based on similarities. |
| taxonomy | Branch of Biology that groups and names of organisms based on studies of their different characteristics. |
| genus | A group of similar species. Org's in the same genus have the potential to produce sterile offspring. |
| family | A group of similar genera (genus). Humans are in "Hominidae". |
| order | A group of similar families. Humans are in "primates". |
| class | A group of similar orders. Humans are in "mammalia". |
| phylum | A group of similar classes. Humans are in "chordata". |
| kingdom | A group of similar phyla or divisions. There are six of these. |
| species | A group of organisms that can interbreed and produce fertile offspring. |
| phylogeny | The evolutionary history of species. |
| eubacteria | Type of bacteria that have very strong cell walls and less complex genetic make-up than found in archaebacteria. |
| protists | Single-celled, eukaryotic organisms that can be autotrophic, heterotrophic or both. |
| fungus | Multicellular, eukaryotic organisms that are heterotrophic by absorption. |
| archaebacteria | "Ancient" bacteria that live in harsh (hot and/or salty) environments. |