Chapter 7 Flashcards
biosphere
the sum total of all of Earth’s ecosystems
ecosystem
all of the organisms in a given area plus the physical environment in which they interact
habitat
the physical environment in which individuals of a particular species can be found.
species
a group of plants or animals that have a high degree of similarity and can generally only interbreed among themselves
niche
the role a species plays in its community, including how it gets its energy and nutrients, what habitat requirements it has, and what other species and parts of the ecosystem it interacts with.
energy flow
the one-way passage of energy through an ecosystem
nutrient cycles
movement of life’s essential chemicals of nutrients through an ecosystem (aka biogeochemical cycles)
biomass
the sum of all organic material - plant and animal matter - that make up an ecosystem
biome
one of many distinctive types of ecosystems determined by climate and identified by the predominant vegetation and organisms that have adapted to live there.
limiting factor
the critical resource whose supply determines the population size of a given species in a given biome.
range of tolerance
the range, within upper and lower limits, of a limiting factor that allows a species to survive and reproduce.
biotic
the living (organic) components of an ecosystem, such as the plants and animals and their waste (dead leaves, feces).
abiotic
the nonliving components of an ecosystem, such as rainfall and mineral composition of the soil.
reservoirs (or sinks)
abiotic or biotic component of the environment that serves as a storage place for cycling nutrients.
producer
an organism that converts solar energy to chemical energy via photosynthesis.
consumer
an organism that obtains energy and nutrients by feeding on another organism.
cellular respiration
the process in which all organisms break down sugar to release its energy, using oxygen and giving off CO2 as a waste product.
carbon cycle
movement of carbon through biotic and abiotic parts of an ecosystem. Carbon cycles via photosynthesis and cellular respiration as well as in and our of other reservoirs such as the oceans and soil. It is also released by human actions such as fossil fuel burning.
nitrogen cycle
continuous series of natural processes by which nitrogen passes from the air to the soil, to organisms, and then returns back to the air or soil through decomposition or denitrification.
nitrogen fixation
conversion of atmosphere nitrogen into a biologically usable form, carried out by bacteria found in soil or via lightning.
phosphorous cycle
series of natural processes by which the nutrient phosphorous moves from rock to soil or water, to living organisms, and back to the soil.
