| A | B |
| weather | the day to day condition of the Earth’s atmosphere at a particular time and place |
| climate | the average, year after year conditions of temperature and precipitation in a particular region |
| greenhouse effect | heat retention by the atmospheric gases of the Earth |
| polar zone | cold areas of Earth between 66.5º and 90º North and South |
| temperate zone | areas of seasonal heat and cold between 23.5º and 66.5º North and South |
| tropical zone | area of year round warmth between 0º and 23.5º North and South |
| biotic factor | living factors in an ecosystem |
| abiotic factor | physical or nonliving factors in an ecosystem |
| habitat | the area where an organism lives |
| niche | full range of physical and biological conditions in which and organism lives and the way in which the organism uses those conditions to survive |
| resource | any factor necessary for life, such as light, water, space, nutrients etc. |
| competitive exclusion principle | no two species can occupy the same niche in the same habitat at the same time |
| predation | interaction in which one organism captures and feeds on another organism |
| symbiosis | any relationship between two different species that live together closely |
| mutualism | symbiotic relationship in which both species benefit |
| commensalism | symbiotic relationship in which one species benefits and the other species is neither benefited nor harmed |
| parasitism | symbiotic relationship in which one species benefits and the other species is harmed |
| ecological succession | a series of predictable changes that occurs in a community over time where the older inhabitants die out and are replaced by new organisms |
| primary succession | primary succession |
| biome | a complex terrestrial community covering a large area that is characterized by certain soil and climate conditions and houses particular groups of plants and animals |
| tolerance | the ability to survive and reproduce in conditions that are different |
| deciduous | trees that shed their leaves during a particular season each year |
| coniferous | trees that produce seed bearing cones and have needle shaped leaves |
| taiga | dense northern evergreen forests |
| permafrost | layer of permanently frozen soil characteristic of the tundra |
| plankton | tiny free floating or weak swimming organisms of aquatic environments |
| detritus | tiny particles of organic material derived from decaying organisms |
| photic zone | well lit upper layer of the ocean in which photosynthesis can occur, no deeper than 200 m |
| aphotic zone | the permanently dark region of the oceans where light never reaches, below 200 m |
| tropical rain forest | biome characterized by rainy humid warm climate all year long |
| tropical savanna | biome characterized by more seasonal rainfall than a desert but less than the dry forest, main plants are grasses |
| desert | biome characterized by less than 25 cm of precipitation per year, temperatures may vary |
| temperate grassland | biome characterized by a rich mix of grasses and cold winters and warm summers |
| temperate forest | biome characterized by by mixture of deciduous and coniferous trees, warm summers and cold winters |
| tundra | biome characterized by permafrost, short cool summers, long cold winters |