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37 terms

biology test chapter 37

ecosytems, trophic levels, carbon, phosphorus, nitrogen cycles, etc.
STUDY
PLAY
All the organisms in a particular area make up a(n) _____.
community
According to the principle of competitive exclusion, two species cannot continue to occupy the same _____.
ecological niche
In terms of + (this member of a species pair benefits from the interaction), - (this member of a species pair is harmed by the interaction), and 0 (this member of a species pair is unaffected by the interaction), predation can be described as a _____ relationship.
+/-
The ecological relationship between termites and the wood-digesting protozoans that live in their gut is an example of _____.
mutualism
During ecological succession, the species composition of a plant community _____.
changes gradually because each species responds differently to changes in environmental factors
The energy for nearly every organism in almost every ecosystem ultimately comes from _____.
the sun
An organism's "trophic level" refers to _____. (
what it eats
Consider this segment of a food web: Snails and grasshoppers eat pepper plants; spiders eat grasshoppers; shrews eat snails and spiders; owls eat shrews. The shrew occupies the trophic level(s) of _____.
secondary and tertiary consumers
What generally flows in one direction through an ecosystem, from producers up through each level of consumers, and is not recycled?
energy
Which of the following ecosystems would probably have the highest primary productivity? Assume that we are comparing similar sizes of each ecosystem.
a tropical coral reef
Biogeochemical cycles are crucial to ecosystem function because _____.
nutrients and other life-sustaining molecules are in limited supply and must be continually recycled
An ecosystem is unlikely to be limited by the supply of _____ because it is obtained from the air.
carbon
The main cause of the recent increase in the amount of carbon dioxide in Earth's atmosphere is _____.
the burning of larger amounts of wood and fossil fuels
community
a population of organisms living close enough together for potential reaction
interspecific interactions
relationships with individuals of other species in the community
interspecific competition
when populations of two different species compete for the same limited resource
mutualism
both benefit
predation
one benefits, one is harmed
herbivory
one benefits, one is harmed
parasitism (pathogens too)
one benefits, one is harmed
commensalism
one benefits, one has no difference
producers
(at bottom) the trophic level that supports all others, usually plants
primary consumers
eat the producers, herbivores
secondary consumers
eat the primary consumers (herbivores), small mammals
tertiary consumers
eat the secondary consumers, a little larger animal
quaternary consumers
(at top) eat the tertiary consumers, in terrestrial ecosystems
detritivores and decomposers
get energy from dead material (detritus)
detritus
dead material, feed detritivores and decomposers
decomposition
breakdown of organic materials to inorganic ones
ecological succession
biological community change
primary succession
lifeless area with no soil
secondary succession
a disturbance destroyed an existing community, but left the soil intact
ecosystem
consists of all organisms in a community and the abiotic environment and the organisms interact
biogeochemical cycle
an ecosystem that includes biotic and abiotic components
abiotic reservoir
atmospheric
biotic reservoir
geological
nitrogen fixation
performed by some bacteria, converts nitrogen to compound of nitrogen that can be used by plants