Select the correct statement describing the nitrogen cycle.
Nitrogen-fixing microbes provide energy for carbon fixation.
Denitrifying bacteria reduce ammonia (NH3 +) to molecular nitrogen (N2).
Bacteria obtain energy from nitrification.
Food chains are sometimes short because
most producers are inedible.
most of the energy in a trophic level is lost as it passes to the next higher level.
predator species tend to be less diverse and less abundant than prey species.
local extinction of a species causes extinction of the other species in its food chain.
only a single species of herbivore feeds on each plant species.
Select the correct statement(s) about the transfer of food energy up the trophic levels from its source in autotrophs.
Select all that apply.
Few plants have adaptations to reduce feeding by herbivores.
The length of a food chain is limited by the inefficiency of energy transfer along the chain.
An organism feeds at only one trophic level.
Which of the following organisms is incorrectly paired with its trophic level?
The observation that members of a population are uniformly distributed suggests that
the members of the population are competing for access to a resource.
the size of the area occupied by the population is increasing.
resources are distributed unevenly.
the members of the population are neither attracted to nor repelled by one another.
the density of the population is low.
amost of the energy in a trophic level is lost as it passes to the next higher level.
bBacteria obtain energy from nitrification.
dthe members of the population are competing for access to a resource.
eThe length of a food chain is limited by the inefficiency of energy transfer along the chain
5 Multiple Choice Questions
Calcium levels remained high in the soil of deforested areas.
In each individual, the form of the behavior is determined entirely by genes.
grows at its maximum per capita rate.
two species that have exactly the same niche cannot coexist in a community.
in biomes at different latitudes.
5 True/False Questions
Which of the following statements about human population in industrialized countries is incorrect?
The survivorship curve is Type I.
Average family size is relatively small.
Age distribution is relatively uniform.
The population has undergone the demographic transition.
Life history is r-selected. → effect of grazing intensity by bison on plant species diversity
A recent study of ecological footprints concluded that
it is not possible for technological improvements to increase Earth's carrying capacity for humans.
the ecological footprint of the United States is large because per capita resource use is high.
Earth's carrying capacity would increase if per capita meat consumption increased.
current demand by industrialized countries for resources is much smaller than the ecological footprint of those countries.
Earth's carrying capacity for humans is about 10 billion. → the ecological footprint of the United States is large because per capita resource use is high.
The feeding relationships among the species in a community determine the community's
ecological niche. → Estimates of the global carrying capacity for the human population depend on resource use per capita.
Suppose that the number of bird species is determined mainly by the number of vertical strata found in the environment. If so, in which of the following biomes would you find the greatest number of bird species?
The majority of young, inexperienced Western garter snakes born in the laboratory from mothers captured in coastal areas of California readily eat pieces of slug. What are plausible proximate explanations for this behavior?
Select all that apply.
Coastal snakes can detect odor molecules produced by banana slugs.
Coastal snakes have a genetically acquired taste for banana slugs.
Coastal snakes that readily eat banana slugs gain most of their calories from this prey species. → Changes in the behavior of cross-fostered young provide information about how the social and physical environment influences behavior.
Cross-fostering studies provide information about the relative importance of nature and nurture in the development of a trait.