5 Written Questions
5 Matching Questions
- dominant species
- trophic structure
- intermediate disturbance hypothesis
- rivet model
- ecological niche
- a The concept that moderate levels of disturbance can foster greater species diversity than low or high levels of disturbance.
- b The different feeding relationships in an ecosystem, which determine the route of energy flow and the pattern of chemical cycling.
- c The concept that many or most of the species in a community are associated tightly with other species in a web of life. According to this model, an increase or decrease in one species in a community affects many other species.
- d The sum total of a species use of the biotic and abiotic resources in its environment.
- e Those species in a community that have the highest abundance or highest biomass. These species exert a powerful control over the occurrence and distribution of other species.
5 Multiple Choice Questions
- A species that is not necessarily abundant in a community yet exerts strong control on community structure by the nature of its ecological role or niche.
- The dry weight of organic matter comprising a group of organisms in a particular habitat.
- The concept that the length of a food chain is limited by the inefficiency of energy transfer along the chain.
- The concept that most of the species in a community are not tightly coupled with one another (that is, the web of life is very loose). According to this model, an increase or decrease in one species in a community has little effect on other species, which operate independently.
- A model of community organization in which predation controls community organization because predators control herbivores, which in turn control plants, which in turn control nutrient levels; also called the trophic cascade model.
5 True/False Questions
mutualism → A symbiotic relationship in which the symbiont benefits but the host is neither helped nor harmed.
integrated hypothesis → The concept that a community is an assemblage of closely linked species, locked into association by mandatory biotic interactions that cause the community to function as an integrated unit, a sort of superorganism.
ectoparasite → A parasite that feeds on the external surface of a host.
commensalism → A symbiotic relationship in which the symbiont benefits but the host is neither helped nor harmed.
facilitator → A species that has a positive effect on the survival and reproduction of other species in a community and that contributes to community structure.