Unit 1-APES
Decreased by the breakdown of organic waste
Dissolved Oxygen
Approximate efficiency of the conversion of light energy to chemical energy in photosynthesis
1%
The maximum efficiency possible in an energy-conversion process that is not limited by the second law of thermodynamics
100%
Approximately what percent of the water on Earth is freshwater (liquid and solid)?
2.5%
The net annual primary productivity of a particular wetland ecosystem is found to be 8,000 kcal/m2 per year. If respiration by the aquatic producers is 12,000 kcal/m2 per year, what is the gross annual primary productivity for this ecosystem, in kcal/m2 per year?
20,000
According to the graph, the increase in CO2 concentration, in parts per million, between 1970 and 1990 is closest to...
30 ppm
Algae in an aquatic food chain convert solar energy into 93,000 kilocalories of plant tissue. Which of the following values best represents the amount of energy available for secondary consumers in the food chain?
930 kilocalories
Which of the following best explains why terrestrial trophic pyramids usually do not have levels higher than tertiary consumers?
A large proportion of energy is lost as heat as it is transferred up the pyramid, so there is not enough energy available to support another level.
Measured on the pH scale
Acidity
Traveling southward from the Arctic regions of Canada to the tropics of Panama, one passes through several biomes - tundra, coniferous forest, temperate deciduous forest, and tropical rain forest. This pattern of change in vegetation is primarily the result of...
An increase in both mean annual temperature and mean annual precipitation
Plant roots absorb ammonium ions and nitrate ions for use in making molecules such as DNA, amino acids, and proteins
Assimilation
The world region that contains the greatest area of rain forest is
Brazil and Indonesia
Elements that cycle in the environment and that also have a gaseous phase at some point in their cycle include which of the following?
Carbon and Sulfur
What is true of carbon as it cycles in nature?
Carbon sinks include forests and oceans
Exemplified by moss growing on a tree trunk in a forest
Commensalism
Exemplified by starlings displacing bluebirds from nesting trees
Competition
Of the following organisms, which occupies the lowest trophic level?
Deer
Nitrate ions and nitrite ions are converted into nitrous oxide gas and nitrogen gas (N2)
Denitrification
The process by which a soil nutrient is reduced and released to the atmosphere as a gas
Denitrification
Which of the following best describes the movement of energy in an ecosystem?
Energy is harnessed by producers, and available energy decreases with each trophic level transfer.
Which of the following is a process that indirectly removes carbon from Earth's atmosphere?
Formation of carbonate deposits
Which of the following best describes gross primary productivity in an ecosystem?
Gross primary productivity is the total amount of solar energy captured by producers through photosynthesis over time.
Which of the following best describes the first law of thermodynamics?
In a closed system of constant mass, the energy involved in any physical or chemical change is neither created nor destroyed, but merely changed from one form to another.
What is most likely a significant cause of the general trend indicated by the graph?
Increase in consumption of fossil fuels
Based on the data in the table, if the number of snakes were to suddenly decrease, which of the following changes would most likely occur in the food web of this ecosystem?
Increase in the number of shrews and a decrease in the number of hawks
What best illustrates an abiotic component of the environment affecting a biotic component of the environment?
Low phosphorus content in soil limits the growth of vegetation
Exemplified by bees consuming nectar and carrying pollen from one flower to another
Mutualism
The major reservoirs of nitrogen and sulfur in the biosphere are correctly identified by which of the following?
Nitrogen ---> Sulfur Atmosphere ---> Rocks
Of the following ecosystems, which has the lowest net primary productivity, measured as kilocalories of energy produced per square meter per year?
Open Ocean
Photosynthesis is the major source of which of the following gases in Earth's atmosphere?
Oxygen
Exemplified by ticks feeding on a deer
Parasitism
The process in which glucose is synthesized by plants
Photosynthesis
The two major processes involved in the carbon cycle are...
Photosynthesis and Respiration
The major biological source of dissolved oxygen in the ocean comes from...
Photosynthesis by phytoplankton
The greatest amount of fresh water is found in which of the following?
Polar ice caps and glaciers
In a typical forest ecosystem, dead trees and fallen trees are most important because of their role in....?
Providing habitats for wildlife
Country with the largest area of boreal forest
Russia
Requires minimum safety standards for community water supplies
Safe Drinking Water Act
The annual fluctuation in carbon dioxide concentration can best be explained by the...
Seasonal photosynthetic activity of green plants
An energy transformation occurs and results in increased disorder.
Second law of thermodynamics
The location of the greatest remaining natural biodiversity...
South America
The ultimate source of energy for terrestrial ecosystem is
The Sun
Losses of usable energy between successive trophic levels in an ecosystem are best accounted for by which of the following?
The second law of thermodynamics
What best describes soil in many tropical rain forests?
They are quickly depleted nutrients when the forest is removed
The process in the hydrologic cycle in which water vapor is released from leaves into the atmosphere is called...
Transpiration
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
Country with the largest area of temperate deciduous forest
United States of America
