Ecosystem
Why is upwelling an important process in a marine ecosystem?
A. Upwelling replaces sand and gravel on beaches lost as the result of wave and tidal action
B. Upwelling decreases the temperature differences between layers of ocean water
C. Upwelling cycles nutrients from decomposers along the ocean floor to producers in surface waters
D. Upwelling returns salt to the surface from the benthic zone as part of the global conveyor belt current
C. Upwelling cycles nutrients from decomposers along the ocean floor to producers in surface waters
Biodiversity can include genetic diversity within a population or variation of populations within an ecosystem. Given this information, which of the following is likely to have the MOST biodiversity?
A. a tropical forest
B. an arctic tundra
C. a deciduous forest
D. a residential backyard
A. a tropical forest
In ecosystems where people live, which of the following are MOST likely to cause an increase disease transmitted by water?
A. floods
B. blizzards
C. hailstorms
D. avalanches
A. floods
In the 1930s, the American Great Plains became known as the Dust Bowl because it was the source of huge clouds of dust that covered much of the United States. Which BEST describes the causes of the Dust Bowl?
A. the overuse of fossil fuels and extensive crop irrigation
B a severe drought and the overuse of prairie farmland
C. wide-scale deforestation and gradual climate change
D. a long period of cool weather and a volcanic eruption
B a severe drought and the overuse of prairie farmland
As a result of human activity, many lakes in Florida have increased levels of nutrients that support algal growth. These algae grow very rapidly, then die and decompose. What impact does this overgrowth of algae MOST likely have on the lake ecosystem?
A. the buildup of bottom sediments decreases.
B. The amount of dissolved oxygen decreases.
C. The volume of lake water increases.
D. The number of fish species increases.
B. The amount of dissolved oxygen decreases.
Lawn fertilizers often contain phosphorus. Sometimes these fertilizers runoff into lakes. Once in a lake, the excess phosphorus may affect algal growth and cause eutrophication in the lake. Which BEST describes how the phosphorus affects the algae?
A. it reduces algae habitat size
B. it improves algae adaptability
C. it increases the carrying capacity of lakes for algae
D. it increases the number of trophic levels algae occupy
C. it increases the carrying capacity of lakes for algae
Which of these living things in a grassland ecosystem depend on the presence of a variety of bacteria and other microorganisms in the soil?
A. worms only
B. green plants only
C. plants and animals only
D. all the organisms in the ecosystem
D. all the organisms in the ecosystem
As human population increase, more shelter is needed. Increasing shelter often requires making a trade-off with another resource. In which case is a food resource decreased to increase a shelter resource?
A. Farmland is converted into house lots
B. Old-growth timber is cut to build houses
C. Corn is made into ethanol for cars instead of food
D. wind power generation on farmland provides electricity for a factory
A. Farmland is converted into house lots
Which phenomenon is BEST demonstrated when a population of deer exceeds the carrying capacity of its environment before setting into equilibrium with the environment?
A. genetic drift
B. natural selection
C. Species overshoot
D. biological magnification
C. Species overshoot
Most of the trash in the United States is currently disposed of in one of three ways:
Which change would decrease the ecological footprint of a town MOST?
A. Increases in recycling and incineration and a decrease in landfill use
B. A decrease in recycling and increases in incineration and landfill use
C. Decreases in recycling and landfill use and an increase in incineration
D. An increase in recycling and decreases in incineration and landfill use
D. An increase in recycling and decreases in incineration and landfill use
When high winds knocked down pine trees in a wooded region, it created a gap in the crowded canopy and allowed sunlight to fall on the ground. The increased sunlight allowed a dense growth of raspberry plants which protected young pine seedlings from being eaten by herbivores. Over time, the pine seedlings grew and blocked sunlight from falling on the woodland floor, thereby preventing growth of more raspberry plants. Which of these terms BEST describes the process of change observed in the woodlands community?
A. adaptation
B. cooperation
C. natural selection
D. ecological succession
D. ecological succession
What is the main reason for concern about the destruction of coral reefs related to global warming?
A. The most colorful fish live in coral reefs
B. Coral reefs are ideal locations for studying marine life
C. Hundreds of thousands of species depend on coral reefs
D. Coral reefs can reduce shoreline damage form tsunamis
C. Hundreds of thousands of species depend on coral reefs
Can Earth’s human population increase indefinitely?
A. yes even though resources are finite
B. yes, because resources are infinite
C. no, even though resources are infinite
D. no, because resources are finite
A. yes even though resources are finite
Which statement BEST explains why only 10% of the energy produced is transferred to the next trophic level?
A. Only a small percentage of energy is needed at higher levels
B. Amount of energy remains the same but in different forms
C. All the energy is used up by primary producers
D. The energy is lost as heat to the environment
D. The energy is lost as heat to the environment
Which statement describes an aspect of tectonic plate motion directly caused by density differences among tectonic plates?
A. The orientation of magnetic particles in oceanic plates changes at regular intervals
B. Continental plates are thicker and contain older material than oceanic plates
C. When oceanic and continental plates collide, the oceanic plate is subducted
D. Oceanic plates move outward from the mid-ocean ridge
C. When oceanic and continental plates collide, the oceanic plate is subducted
After a volcanic eruption, ecosystems undergo a series of events known as succession. A study done by ecologists on Mount St. Helens concludes that primary succession occurs when lupines are able to enrich the soil. Lupines are a nitrogen-fixing plant well adapted to colonizing sterilized ecosystems. However, the progression of the lupine is slowed by a certain predatory caterpillar. What would be the MOST successful strategy for ensuring succession in an area where lupines and the caterpillars both colonize?
A. replace the lupines with another type of plant
B. move the caterpillar populations to a different area
C spread the lupine seeds to increase the density of growth
D. introduce a controlled fire to begin secondary succession
C. spread the lupine seeds to increase the density of growth
Solid waste in the ocean can threaten different marine species in many different ways. Many communities are working to reduce solid waste. Which of the following actions would MOST help to protect marine species that eat jellyfish?
A. banning plastic bags
B. recycling plastic bottles
C. composting cardboard containers
D. requiring a deposit on glass
A. banning plastic bags
Which statement BEST explains the flow of energy as it moves through the different levels?
A. Energy decreases as it is lost as heat to the environment
B. Energy increases as it is gained from the environment
C. Energy is unavailable because it is used up by the organisms at Level 1
D. Energy is transferred as it produced by organisms in the next level
A. Energy decreases as it is lost as heat to the environment
Secondary succession is a process that reestablishes a previously colonized, but disturbed or damaged habitat. Which will MOST likely result in colonization by large herbivores and carnivores?
A. saplings and trees
B. grasses and shrubs
C. lichens and mosses
D. seedlings and bushes
D. seedlings and bushes
To which of the following phenomena do humans contribute the least?
A. Air pollution
B. Deforestation
C. Soil erosion
D. Plate tectonics
D. Plate tectonics
Tundra biomes are found in the northern polar region. The ground is frozen from deep underground nearly to the surface. The thin layer of soil allows small plants with shallow roots to grow. However, it is believed that global warming might cause tundra ground to thaw to a greater depth, allowing larger plants to grow. If this occurs, animal populations in the tundra could be expected to increase. Which BEST explains why animal populations could increase?
A. Territory would increase in size.
B. A limiting factor would become more available
C. Nutrients would cycle more quickly to decomposers
D. An ecologically warmer habitat would increase oxygen rates
B. A limiting factor would become more available
Dall sheep have adapted to live in alpine tundra ecosystems. Alpine tundra has cold temperatures, steep terrains, and limited availability of food sources. Which BEST explains what would happen to the Dall sheep if the alpine tundra ecosystem became much warmer?
A. There would be an increase in predators moving into the ecosystem
B. Sheep populations would move down the mountains to a new habitat
C. Environmental stressors would increase the fitness of the sheep
D. Genetic variability would increase due to a low carrying capacity of the ecosystem
D. Genetic variability would increase due to a low carrying capacity of the ecosystem
Materials such as carbon and nitrogen go through cycles. The cycling of nitrogen waste materials is mostly dependent upon the role of which factor?
A. atmosphere
B. bacteria
C. sunlight
D. trees
B. bacteria
Which is the BEST example of a community responding to an external factor?
A. Plants and animals thrive on the forest floor after the fall of a white pine causes an opening in the canopy.
B. Many species of raptors fly alongside each other during the autumn migration to warmer climates.
C. Elephants use their tusks to dig the salt needed in their diets from the wall of a cave.
D. Adult musk oxen in a herd surround their young to protect them from wolves.
D. Adult musk oxen in a herd surround their young to protect them from wolves.