| Term | Definition |
| classification | process of grouping things based on their shared traits |
| taxonomy | scientific study of how living things are classified |
| binomial nomenclature | the system that Linnaeus devised which assigns each organism a two-part name |
| genus | the first part of an organism's scientific name; a group that contains similar, closely related organisms |
| species | the second part of an organism's scientific name; a group of similar organisms that can mate and produce fertile offspring |
| flagellum | a long, whip-like structure that moves some bacteria from place to place |
| binary fission | the process by which one cell divides to form two new identical cells; how some bacteria reproduce |
| endospore | a small, thick-walled, resting cell that forms inside a bacterial cell; it forms when bacteria are in an unfavorable environment |
| decomposer | organisms that break down large molecules in dead organisms into smaller molecules |
| protozoan | animal-like protists |
| pseudopod | temporary bulges of the cell membrane that protozoa use to move |
| cilia | hairlike projections from cells that move with a wavelike pattern |
| parasite | organisms that live on or in other organisms and harm them |
| host | the organism that a parasite lives on |
| algae | the common name for plant-like protists |
| spore | a tiny cell that is able to grown into a new organism |
| hyphae | branching, thread-like tubes that make up bodies of multicellular fungi |
| budding | a small cell grows from the body of a large parent cell |
| vascular tissue | an internal system of tube-like structures in plants that carry water, minerals and food |
| stomata | pores in a leaf that control the movement of gases into and out of a leaf |
| fertilization | when a sperm cell unites with an egg cell |
| zygote | the fertilized egg |
| embryo | an organism that develops from a zygote |
| seed | a structure that contains a young plant inside a protective covering |
| cotyledon | a seed leaf that stores food |
| pollen | tiny particles produced by plants that contain the microscopic cells that later become sperm cells |
| ovule | a structure that contains an egg cell |
| flower | where the seeds are produced in angiosperm |
| stamen | the male reproductive part of an angiosperm (flowering plant) |
| pistil | the female reproductive part of an angiosperm (flowering plant) |
| fruit | a ripened ovary and other structures that enclose one or more seeds |
| tropism | a plant's growth response toward or away from a stimulus |
| hormone | a chemical produced inside an organism that affects the organism's body processes such as growth and development |
| adaptation | a characteristic that helps an organism survive in its environment and reproduce |
| herbivore | animal that eats only plants |
| carnivore | animal that eats only other animals |
| predator | animal that hunts and kills other animals |
| prey | animal that gets hunted and killed by a predator |
| omnivore | animal that eats both plants and other animals |
| invertebrate | animal that does not have a backbone |
| vertebrate | animal that has a backbone |
| prokaryote | an organism whose cell does not contain a nucleus |
| eukaryote | an organism whose cell does contain a nucleus |
| autotroph | an organism that makes it's own food |
| heterotroph | an organism that cannot make it's own food |
| archaebacteria and eubacteria | Kingdoms with prokaryotes |
| protists, fungi, plants, animals | Kingdoms with eukaryotes |
| archaebacteria, eubacteria, some protists, some fungi | Kingdoms with unicellular organisms |
| some protists, some fungi, plants, animals | Kingdoms with multicellular organisms |
| some archaebacteria, some eubacteria, protists, plants | Kingdoms with autotrophic organisms |
| some archaebacteria, some eubacteria, protists, fungi, animals | Kingdoms with heterotrophic organisms |
| algae | the common name for plant-like protists |
| protozoan | the common name for animal-like protists |
| positive tropism | a plant growing toward a stimulus |
| negative tropism | a plant growing away from a stimulus |