PCB3043 Questions and Correct Answers
commensalism Ans: An interaction where one species benefits
and the other is unnafected (feeder, shelter, transportation,
habitat, and dispersal)
mutualism Ans: A direct or indirect species interaction where
both species benefit
allelopathy Ans: a phenomenon when an organism produce
biochemicals that affect the growth, survival, and reproduction of
other organisms
integrated pest management Ans: an intergrated approach of crop
management to solve ecological problems when applied in
agriculture; main goal is to reduce or eliminate the use of
pesticides while managing pest populations
community Ans: "An assemblage of populations of living
organisms is a prescribed area or habitat that interact with one
another, directly, or indirectly"
ecosystem Ans: all the organisms living in a particular area, as
well as all the nonliving, physical compounds of the environment
with which the organisms interact, including air, soil, water, and
sunlight
association Ans: group of species living in the same place
guild Ans: species in the same community using resources in the
same way, often competitors
phytosociology Ans: the study of the composition and structure
of plant communities
diversity Ans: Species evenness is high, or species richness
(number of species in a community) is high
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alpha diversity Ans: with-in habitat diversity, number of species
in local small areas of uniform habitat
beta diversity Ans: between habitat diversity, the variation in
species composition from one habitat to another within a region
gamma diversity Ans: regional diversity, number of species in a
larger area of interest across habitats or local areas
indirect mutualism Ans: Occur when more than two species
interact such that one benefits another by way of its impact on a
third species
facilitation Ans: occurs when one species changes the
environment to be more suitable for a second species; an indirect
form of commensalism
richness Ans: the number of species in a community
top predators Ans: species that get eaten by nothing else in the
food web
basal predators Ans: species that feed on nothing within the web.
(usually plants for green community)
omnivores Ans: species that feed at more than one trophic level
connectance Ans: number of actual interactions divided by the
number of possible interactions
food chain length Ans: A method a quantifying food chains based
on the number of trophic levels
cannibals Ans: a cycle in which species feed upon itself
trophic levels Ans: each of the heirarchal levels in an ecosystem
trophic species Ans: groups of species that have the same
predator and prey
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