Nonliving; specifically, the nonliving components of an ecosystem, such as temperature, humidity, the mineral content of the soil, etc.
The process in which pyruvic acid is broken down and NADH is used to make a large amount of ATP; the part of respiration that is carried out in the presence of oxygen.
The use of inorganic molecules other than oxygen to accept electrons at the "downhill" end of electron transport chains.
A mixture of gases that surround the Earth
Organisms that use energy from sunlight or inorganic substances to make organic compounds
The pathways by which chemicals circulate through ecosystems that involve both living (biotic) and nonliving (geological) components.
A measure of the total dry mass of organisms within a particular region
The entire portion of Earth inhabited by life; the sum of all the planet's ecosystems.
Pertaining to life; environmental factors created by living organisms
Cyclic movement of carbon in different chemical forms from the environment to organisms and then back to the environment.
Organisms that eat other animals for energy
Process in which certain organisms (mostly specialized bacteria) extract inorganic compounds from their environment and convert them into organic nutrient compounds without the presence of sunlight. Compare photosynthesis.
All the organisms that inhabit a particular area; an assemblage of populations of different species living close enough together for potential interaction.
Organisms that eat living producers and/or other consumers for food
Organisms that break down the dead remains of other organisms.
Commonly digest decomposers that live on, and in, detritus particles, which they chew and grind into even smaller pieces.
The study of how living things interact with each other and their environment
All the organisms in a given area as well as the abiotic factors with which they interact; a community and its physical environment
A catabolic process that makes a limited amount of ATP from glucose without an electron transport chain and that produces a characteristic end product, such as ethyl alcohol or lactic acid.
Series of steps in an ecosystem in which organisms transfer energy by eating and being eaten.
Anticipated increase in Earth's temperature, caused by carbon dioxide (emitted by burning fossil fuels) trapping some of the radiation emitted by the surface.
Gross Primary Productivity (GPP)
The rate at which an ecosystem's producers capture and store a given amount of chemical energy as biomass in a given length of time. Compare net primary productivity.
Organisms that obtain energy by eating only plants
Organisms that rely on other organisms for their energy and food supply
Hydrologic (water) cycles
Continuous movement of water on, above and below the surface of the Earth.
The earth's liquid water (oceans, lakes, other bodies of surface water, and underground water), frozen water (polar ice caps, floating ice caps, and ice in soil, known as permafrost), and water vapor in the atmosphere. See also hydrologic cycle.
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 (NPP)
Rate at which all the plants in an ecosystem produce net useful chemical energy; equal to the difference between the rate at which the plants in an ecosystem produce useful chemical energy (gross primary productivity) and the rate at which they use some of that energy through cellular respiration. Compare gross primary productivity.
The recycling of nitrogen in the environment in which nitrogen goes from a gas, to organic compounds in the soil, to proteins in a plant or nitrates, and then is again released into the atmosphere as a gas.
Nutrient (biogeochemical) cycles
The elements and compounds that make up nutrients move continually through air, water, soil, rock and living organisms in ecosystems and in the biosphere
A consumer that eats both producers and other consumers
An animal or plant with organs that function together to maintain life; a living thing; anything that resembles a living thing in structure or function
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.
Cyclic movement of phosphorus in different chemical forms from the environment to organisms and then back to the environment
A group of individuals of the same species that live together in the same area at the same time
Organisms that are unable to produce their own energy. They must eat producers to obtain energy. Also called: consumers.
Organisms that produce 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.
The carnivores in an ecosystem; organisms that feed on primary consumers
The layer of Earth's atmosphere that extends from the troposhere to the mesosphere; concentrations of ozone cause it to get warmer as you go up in this layer.
Cyclic movement of sulfur in different chemical forms from the environment to organisms and then back to the environment.
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.
All organisms that are the same number of energy transfers away from the original source of energy (for example, sunlight) that enters an ecosystem. For example, all producers belong to the first trophic level, and all herbivores belong to the second trophic level in a food chain or a food web.
The lowest layer of the atmosphere, in which temperature drops at a constant rate as altitude increases; the part of the atmosphere where weather conditions exist