features of the environment that are alive or were once alive
nonliving, physical features of the environment, including air, water, sunlight, soil, temperature, and climate
air surrounding Earth; is made up of gases, including 78 % nitrogen, 21 % oxygen, and 0.03% carbon dioxide
mixture of mineral and rock particles, the remains of dead organisms, air, and water that forms the topmost layer of Earth's crust and supports plant growth.
average weather conditions of an area over time, including wind, temperature, and rainfall or other types of precipitation such as snow or sleet.
process that takes place when a liquid changes to a gas
process that takes place when a gas changes to a liquid
model describing how water moves from Earth's surface to the atmosphere and back to the surface again through evaporation, condensation, and precipitation
process in which some types of bacteria in the soil change nitrogen gas into a form of nitrogen that plants can use
model describing how nitrogen moves from the atmosphere to the soil, to living organisms, and then back to the atmosphere
model describing how carbon molecules move between the living and nonliving world.
process in which producers make energy-rich nutrient molecules from chemicals
model that shows the complex feeding relationships among organisms in a community
model that shows the amount of energy available at each feeding level in an ecosystem