| A | B |
| ecology | study of interactions between organisms & their environment |
| biosphere | all parts of Earth that supports life |
| ecosystem | organisms and their nonliving environment |
| community | all the interacting organisms in an area |
| population | all the members of one species living in a particular place |
| habitat | place where an organism lives |
| biotic factor | living components of the environment |
| abiotic factor | nonliving components of the environment |
| niche | the specific role or way of life for an organism in its environment |
| generalists | organisms with broad niches |
| specialists | orgnanisms with narrow niches |
| producer | organism that capture sunlight energy to make their own food |
| biomass | all the organic material in an ecosystem |
| net primary productivity | rate at which biomass accumulates in an ecosystem |
| consumer | organism that eats other organisms for its energy |
| herbivore | an organism that eats producers |
| carnivore | organism that eats other consumers |
| omnivore | organism that eats both producers and consumers |
| detritivore | organism that feeds on the garbage of the ecoystem |
| decomposer | organism that breaks down complex organic molecules into simpler inorganic molecules |
| trophic level | an organisms position in a sequence of energy tranfers |
| food chain | a single pathway feeding relationship |
| food web | multiple pathways of interrelated feeding relationships |
| biogeochemical cycle | recycling of matter in an ecosystem |
| transpiration | evaporation of water from leaves |
| nitrogen fixation | taking N2 gas and making it into NH3 (ammonia) |
| nitrogen-fixing bacteria | organisms that convert N2 into NH3 (ammonia) |
| ammonification | converting organism wastes into NH3 (ammonia) |
| nitrification | converting of NH3 (ammonia) into NO3 (nitrates) |
| denitrification | converting NO3 (nitrates) into N2 atmospheric gas |