Units 0-1 Environmental science test answers

Scientists are closely monitoring the caribou populations to examine the effect of global climate change on habitat. The maximum population size for a herd of caribou based on the amount of habitat was 500,00. A herd of caribou currently has a population size of 198,000 caribou caribou as a result of habitat loss. Which of the following methods should be used to determine the percent change between the maximum population and the current population for this herd of caribou?

(198,000 caribou - 500,000 caribou) / 500,000 x 100

The change in present-day Co2 concentration as compared to the Co2 concentration 22,000 years ago?

1.6 times greater

Based on the data from the graph, which of the following indicates how much more effective oxygen transport is at the 20 percent carbon monoxide level than the 60 percent carbon monoxide level?

1.9 times more effective

The graph below shows the average pH of precipitation from several regions of the world. Approximately, how many more times acidic is precipitation in the northeastern United states as compared to precipitation in the south pacific?

10

Based on the laws of thermodynamics, which of the following is the applied mathematical routine used to estimate the biomass of the mice in the pyramid?

18,705 x 0.10 x 0.10

A soil sample near Chernobyl was found to contain 187/kBq/m2 of cesium-137. If the half life of cesium-137 is approximately 30 years, how much cesium-137 will remain in the sample after 90 years?

23.38 kBq/m^2

Primary producers in a lake ecosystem store approximately 25,000 kcal/m2/yr of energy in their biomass. Which of the following identifies the most likely amount of energy available to a tertiary consumer in this ecosystem?

25 kcal/m2/yr

The net primary production of a pine forest on a lava flow on Mount Fuji is about 175,000 kcal/m2/yr, and the plant respiration is estimated to be 115,000 kcal/m2/yr. What is the total amount of energy transferred during photosynthesis for this ecosystem?

290,000 kcal/m2/yr

A vehicle releases 1.39 grams Nox per mile. If the vehicle drove 22,000 miles per year for 15 years, how much Nox does that vehicle release?

458,700

The atmospheric concentration of carbon dioxide increased from 278 ppm in 1790 to 424 ppm in 2023. What is the approximate percent increase in carbon dioxide concentration from 1790 to 2023?

53%

If an area was originally forested and then underwent urban development, which of the following shows the most likely effects on various parts of the water cycle in the area?

A

A field is abandoned, and an invasive plant that can live in nutrient-poor soil moves into the field. If the land is later cleared of this invasive species and it is discovered that the soil has an abundance of nitrogen compounds, what conclusion can best be made?

Bacteria in soil and in root nodules converted free nitrogen into nitrogen compounds.

Which of the following is true of carbon as it cycles in nature?

Carbon sinks include forests and oceans

How does the burning of fossil fuels contribute to the net increase in atmospheric carbon?

Carbon that has been sequestered underground is added to the carbon cycling between the atmosphere and the biosphere

Which of the following best explains the data presented in their ecological footprints?

Colder average temperatures and longer nights

Which process in the nitrogen cycle releases nitrogen gas into the atmosphere?

Denitrification of soil nitrates by bacteria

Which of the following best illustrates the concept of the tragedy of the commons?

Depletion of an aquifer by regional farmers

Which sequence of events best explains the interaction between the components of the Arctic ecosystem positive feedback loop?

Global temperature increases -> permafrost thickness decreases -> methane increases -> global temperature increases

Based on the diagram, which group of organisms would be considered herbivores?

Grasshoppers

Open oceans produce the largest share of Earth's biomass because the net primary productivity (NPP) of the oceans is

Low, but the large expanse of the oceans supports enormous numbers of producers such as phytoplankton

Which city had the lowest average per capita ecological footprint?

Ottowa

Which of the following modifications on the graph above would improve the validity of the investigation?

Perform the experiment on a larger sample size of mice

In August of 2014, residents of several Ohio cities that use Lake Erie as a drinking water source were warned not to drink tap water because of the presence of toxins released by blue-green algae (cyanobacteria). Which of the following is the most likely cause of recent blooms of blue-green algae in Lake Erie?

Phosphorus contained in agricultural runoff

The graphs below show inputs of several different pollutants into the Chesapeake bay from four major river systems. Which of the following strategies will best reduce eutrophication in the Chesapeake bay?

Regulating the use of inorganic fertilizer in the Susquehanna River watershed

The graph below shows the monthly average CO2 concentration, in parts per million, as measured at Mauna Loa Observatory in Hawaii. Which of the following most directly explains the periodic fluctuations of the curve?

Seasonal variations in photosynthetic activity

Which of the following is the primary energy source for producers in near-surface marine communities?

Solar energy from the sun

Consumers who get their electricity from coal-fired power plants are not paying the true cost of energy production in their monthly utility bills because externalities are not factored in. Which of the following is true about utility bills for these consumers?

The bills do not include public health costs, such as those associated with air pollution

Construction of a solar power plant is proposed for a desert area near a school. A student has hypothesized that the shade cast by the solar panels will increase the mortality of creosote bush, a native desert plant in the area. Before construction begins, what experimental data should the student collect in order to eventually test the hypothesis?

The direct sunlight received by creosote bush in the desert area (in kWh/m2) during a 12-month period

Scientists are interested in determining the impact of the construction of a hydroelectric dam on a population of salmon that live downstream of a populated area. They measure the health of the salmon population in it's current state, several years after the dam was constructed. Which of the following would be the best to use as a control in this study?

The health of the salmon population prior to any dam construction

The feeding relationships between several marine organisms are shown in the food web below. Based on the diagram, which of the following best describes the most likely direct effect of a decline of the small fish population on the marine food web?

The jellyfish population will increase because of decreased predation.

Which of the following biogeochemical cycles is correctly paired with its largest reservoir?

The nitrogen cycle and the atmosphere.

It has recently been estimated that the growth in world population has slowed in the past decade. Despite this trend, environmentalists remain concerned about the environmental impact of world population, principally because

The standard of living is increasing in many developing countries, leading to an increased per capita use of natural resources

A laboratory experiment was done to show the effects of organic waste on the dissolved oxygen (DO) content in water. Five tanks were set up, each containing fresh water and a small amount of single-celled green algae. Specified amounts of organic waste were added to the tanks. The results below show the amount of DO in each tank after a period of one week. What is the main purpose for the experiment?

To observe the effect of organic waste on DO

Which of the following best helps to explain why phosphorus is often a limiting factor in many ecosystems?

Under many conditions, phosphorus forms stable insoluble compounds

A student reads that nanosilver particles are used in cosmetics to allow nutrients to penetrate deeper into the skin. When the cosmetics are washed off, the nanosilver particles can enter freshwater ecosystems. These particles may decrease survival in many aquatic organisms. The student determines that Daphnia magna, a tiny freshwater crustacean widely found in North America, might make a good test subject for an experiment. Which statement below is the most likely testable hypothesis based on the information provided?

When the concentration of nanosilver particles in the water is increased, the population of Daphnia magna will decrease

Eutrophication results in the death of trout and other fish as a result of

asphyxiation from lack of oxygen

Corn can be grown at a rate of 1,000 kcal per hectare, and it takes 20 times more land to produce beef than it does to produce corn. Which of the following equations would correctly calculate the amount of land needed to produce 10,000 kcal of beef?

end result is x 10,000 kcal beef

For a primary producer, the main function of photosynthesis is to manufacture

glucose

A sustainable society would emphasize

using energy efficiently and reusing and recycling matter

An experiment was carried out to determine the lethal dose of ammonium sulfate on mung bean germination. True statements about the experimental design include which of the following?

||. The independent variable is the concentration of ammonium sulfate |||. The dependent variable is the number of seeds that failed to germinate