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Natalie Cestero


nonliving, physical features of the environment, including air, water, sunlight, soil, temperature, and climate

aerobic respiration

cellular respiration that uses oxygen, sequentially releasing energy and storing it in ATP

anaerobic respiration

the process by which cells obtain energy from an energy source without using oxygen


the mass of air surrounding the Earth


organisms that make their own food

biogeochemical cycles

process in which elements, chemical compounds, and other forms of matter are passed from one organism to another and from one part of the biosphere to another


the total mass of living matter in a given unit area


the regions of the surface and atmosphere of the Earth (or other planet) where living organisms exist


any living or previously living component of an environment

carbon cycle

the organic circulation of carbon from the atmosphere into organisms and back again


Organisms that eat other animals for energy


A few producers, mostly specialized bacteria, can convert simple inorganic compounds from their environment into more complex nutrient compounds without using sunlight, through a process called chemosynthesis.


(ecology) a group of interdependent organisms inhabiting the same region and interacting with each other


an organism that obtains energy and nutrients by feeding on other organisms or their remains.


organisms that break down wastes and dead organisms and return raw materials to the environment


organisms that consume organic litter debris and dung.


the branch of biology concerned with the relations between organisms and their environment


a specific biological community and its physical environment interacting in an exchange of matter and energy.


a process in which an agent causes an organic substance to break down into simpler substances

food chain

a series of steps in which organisms transfer energy by eating and being eaten

greenhouse effect

natural situation in which heat is retained in Earth's atmosphere by carbon dioxide, methane, water vapor, and other gases

gross primary productivity

the rate at which producers in an ecosystem capture energy


an organism that eats only plants.


organisms that cannot make their own food

hydrologic cycles

The cycle through which water in the hydrosphere moves; includes such processes as evaporation, precipitation, and surface and groundwater runoff


the portion of earth that is water

natural greenhouse effect

Heat buildup in the troposphere because of the presence of certain gases, called greenhouse gases. Without this effect, the earth would be nearly as cold as Mars, and life as we know it could not exist. Compare global warming.

net primary productivity

the rate at which biomass accumulates in an ecosystem

nitrogen cycles

other organisms other than plants play a large role in the N cycle (unlike the H20 cycle)
- both cycles can be limited by plant growth and ecosystem productivity
-cycles are functionally linked--> N comes into biosphere from the atmosphere (78% N2) through FIXATION

nutrient cycles

processes that that move nutrients back and forth between the biotic and abiotic environment


an organism that eats both plants and animals.


Any living thing


process by which plants and some other organisms use light energy to convert water and carbon dioxide into oxygen and high-energy carbohydrates such as sugars and starches

phosphorus cycle

The movement of phosphorus atoms from rocks through the biosphere and hydrosphere and back to rocks.


a group of organisms of the same species populating a given area

primary consumers

The herbivores in an ecosystem; organisms that feed on primary producers


organisms that make their own food

pyramid of energy flow

Diagram representing the flow of energy through each trophic level in a food chain or food web. With each energy transfer, only a small part (typically 10%) of the usable energy entering one trophic level is transferred to the organisms at the next trophic level. Compare pyramid of biomass, pyramid of numbers.

secondary consumers

carnivores that eat herbivores


the layer of the atmosphere that is above the troposphere and in which temperature increases as altitude increases

sulfur cycle

Cyclic movement of sulfur in different chemical forms from the environment to organisms and then back to the environment.

tertiary consumers

Animals that feed on animal-eating animals. They feed at high trophic levels in food chains and webs. Examples are hawks, lions, bass, and sharks. Compare detritivore, primary consumer, secondary consumer.

trophic level

step in the movement of energy through an ecosystem; an organism's feeding status in an ecosystem.


the layer of the atmosphere that touches the surfaces of the Earth, contains most of the water vapor

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