Test Unit 2
At which time after clear-cutting does the ecosystem exhibit the greatest species richness?
100 years
The pH at which 50 percent of the Daphnia survive after 2 hours of exposure can be predicted from the data. This pH is closest to
4.5
On the basis of the data, the best prediction of the pH of the water in which Daphnia normally are found in the wild is
7
Which of the following explanations is best supported by the data shown in the map above?
Animals migrate seasonally to mate and to find food in different habitats.
Which of the following would be most likely to occur in the scenarios that have experienced habitat loss and/or fragmentation in the diagram?
Decrease in the number of specialist species
Based on the data in the table, which ecosystem is in the earliest stages of succession?
Ecosystem B
Which of the following best explains how environmental stressors, such as wildfires, can affect biodiversity in an ecosystem?
Ecosystems with more species diversity are more likely to recover after a disturbance than ecosystems with low species diversity.
Which of the following would most likely result from the deforestation of large areas of tropical rain forests caused by slash-and-burn agriculture?
Increased global temperature because of the release of CO2
A research team monitoring a local freshwater ecosystem noticed that over the past few years the otter population had declined significantly, while the populations of other species remained fairly constant. After running tests, the research team determined that mercury levels in invertebrates and small fish in the ecosystem were very high. In this ecosystem, what role did the otters occupy?
Indicator species
Which of the following best explains why each of the finch species on the Galápagos Islands evolved to be specialists?
Islands have limited food resources, forcing species to feed on a small range of food items.
Which of the following best describes the role of moss in the transition to stage III of the process?
It breaks down rock and adds organic nutrients to the soil.
How would including a control group be useful in this experiment?
It would provide a reference for the effects of random environmental factors.
On the coast of Oregon, mussels cover most of the rocky shoreline. Two mussel predators include Pisaster (ochre stars) and Nucella (whelks). A sixty-day removal study was conducted, and the results are presented in the graph. Which of the following conclusions is best supported by the data in the graph?
Pisaster is a keystone species, because when Nucella was removed the proportion of live mussels was similar to the control.
Which of the following best identifies and describes the process that is illustrated in the diagram above?
Primary succession, because the process in the diagram begins with bare rock.
Which of the following likely best describes why most of these species went extinct?
Rapid climate and habitat change
Which of the following best describes why secondary succession generally occurs more quickly than primary succession?
Secondary succession takes place in areas that already have soil and nutrients in place, whereas primary succession occurs in areas that lack soil.
For which of the following reasons do small isolated islands have a greater rate of species extinction than larger, less isolated islands?
Small isolated islands have a lower availability of resources.
Which tree species grows best with full sunlight?
Sweet gum
If the pond is resampled a year later, which of the following would best indicate that the pond had been adversely affected by adjacent development?
The biodiversity of the pond has decreased.
Which of the following best describes the frog species' range of tolerance to acidic conditions?
The frogs can tolerate a pH between 4.5 and 6.
Which of the following statements best describes how the moths adapted to the new environment over time?
The moths adapted to the new environment by changes in the genetics of the population.
Which of the following statements best explains why the Devils Hole pupfish are able to live in this environment?
The pupfish are well adapted to the habitat of Devils Hole and can thrive in conditions that are outside of the range of tolerance for most other species.
Which of the following can be estimated from the sample for the invertebrates in the pond?
The species richness
Which of the following is a measure of the biodiversity of an ecosystem?
The total number of different plant species
Which of the following statements best explains the changes in the size and composition of the population of finches after the drought?
The total number of finches in the population decreased, and the larger-beaked finches were more successful in the drier environment.
The table below shows measurements of the beak size of a sample of ten ground finches on each of two islands in the Galápagos archipelago. The two islands are about ten kilometers apart, and all the birds are the same species. Given that beak size is genetically determined, which of the following hypotheses is the most likely explanation for the differences in data between the islands?
The types of food found on the two islands exert selective pressure on beak size.
Which of the following best describes a supporting ecological service provided by wetlands?
Wetlands provide a habitat for a wide variety of organisms.
Which statement below is the most likely testable hypothesis based on the information provided?
When the concentration of nanosilver particles in water is increased, the population of Daphnia magna will decrease.
Based on the diagram above, in which stage are most species present considered pioneer species?
ll
Small populations of animals, such as those typically found on islands, are prone to extinction because
they are more vulnerable to unpredictable events
