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28 Cards in this Set

  • Front
  • Back
A community is composed of
potentially interacting populations of different kinds of organisms.
When two different populations in a community benefit from their relationship with each other, the result is called ____
Which of the following is an example of predation?
a hawk swooping down quickly to capture, kill, and eat a prairie king snake
The sum total of a population's use of the biotic and abiotic resources of its habitat constitutes its ___.
In an ecosystem, you would expect to find interspecific competition between
populations of two species that occupy the same niche
If an overlap develops between the ranges of two closely related species, and if the species occupy the same niche in the zone of overlap, what will probably happen in the zone of overlap?
One species will take over most or all of the zone of overlap.
Camouflage typically evolves as a result of ___.
One mechanism that prey populations evolve to avoid predation is
chemical defenses.
Some herbivore-plant interactions evolved through a series of reciprocal evolutionary adaptations in both species. The process is called ___.
Most plants have a variety of chemicals, spines, and thorns because the plants
cannot run away from herbivores.
The prokaryotes that cause tooth decay have a ________ relationship with humans.
Within an ecosystem, a tree is a ___.
On Earth, most organic molecules are produced by
In a hypothetical food chain consisting of grass, grasshoppers, sparrows, and hawks, the grasshoppers are
primary consumers
In a food chain consisting of phytoplankton → zooplankton → fish → fishermen, the fishermen are
tertiary consumers.
Organisms that digest molecules in organic material and convert them into inorganic forms are
Which of the following statements regarding food webs is true?
Several species of primary consumers may feed on the same species of producer.
The number of species in a community is called the
species richness.
We expect that a keystone species that is a predator will
maintain the species diversity in a community.
During ecological succession, the species composition of a plant community generally
changes gradually because each species responds differently to the changing environment.
When a New England farm is abandoned, its formerly plowed fields first become weedy meadows, then shrubby areas, and finally forest. This sequence of plant communities is an example of
secondary succession.
Non-native species that are introduced in new environments, spread far beyond the original point of introduction, and cause damage are called
invasive species.
The flow of ________ into ecosystems occurs in one direction only, while ________ are recycled within the ecosystem itself.
energy . . . chemicals
In an average ecosystem, about how much energy is present in the organisms at a given trophic level compared to the organisms at the next higher trophic level?
ten times as much
Which of the following substances is cycled between organic matter and abiotic reservoirs?
Carbon mainly cycles between the biotic and abiotic worlds through the processes of
cellular respiration and photosynthesis.
Which of the following statements about the nitrogen cycle is true?
The nitrogen cycle requires different types of bacteria.
Denitrifying bacteria convert ________ to ________.
nitrates . . . nitrogen gas