Within any one of the biochemical cycles, “flux” refers to:
the rate of transfer from one reservoir to another
In a covalent bond, atoms __________ electrons.
The sodium atom (Na) contains 11 electrons, 11 protons, and 12 neutrons. What is the mass number of sodium?
The pathway by which carbon is transferred from living biota to the atmosphere is called:
The rock cycle depends on the ________ cycle to lift mass above sea level and the ________ cycle to supply the force of erosion.
An element with a gaseous phase under conditions at the surface of the Earth tends to ____________ much more rapidly than an element without a gas phase.
Fluxes of nitrogen both into and out of the atmosphere are controlled predominantly by:
the activity of microscopic bacteria
The tectonic cycle refers to the creation, destruction, and recycling of:
the crust of the earth
The nitrogen cycle is one of the most important biogeochemical cycles. However, molecular nitrogen (N2) in the atmosphere is not a significant element for life because:
N2 is relatively inert and must be transformed to ammonia or other nitrogen compounds in order to be useful
The original source of energy that drives the hydrologic cycle is:
Many higher organisms have evolved symbiotic relationships with nitrogen-fixing microorganisms. This is because:
the microorganisms transform nitrogen into forms useful to the higher organisms
The following chemical equation describes which process: 6CO2 + 6H2O —> C6H12O6 + 6O2
(True or False) The second law of thermodynamics states that energy always changes from a more useful, higher quality form to a less useful, lower quality form.
These organisms live at or near deep ocean vents and derive energy from inorganic sulfur compounds:
Net production equals:
change in biomass over time
Energy efficiency is the:
ratio of energy output to energy input
Photosynthetic autotrophs, at the first trophic level, get their food from:
inorganic chemicals and sunlight
What is meant by energy “fixation”?
the transfer of light energy to energy in chemical bonds of an organic compound
The principle that one species can prepare the way for the next and/or may even be necessary for the occurrence of the next is called:
Biomass refers to the amount of organic matter. The Earth’s biomass may be measured in units of ________. The change in biomass is called ________.
grams per m2; net production
Succession usually occurs:
where a physical, degrading environment dominates
Modern demand-based agriculture involves all of the following characteristics except: 1.artificial use of fertilizer. 2.increased decomposition of soil organic matter. 3.increased CO2 concentrations in the atmosphere. 4. cultivation of subsistence crops. 5. major use of fossil fuels
4. cultivation of substistence crops
The reason that weeds compete so effectively against agricultural crops and must be inhibited or removed is that:
weeds are early successional species and naturally do well on cleared land
According to the Environmental Science text, what is the key to food production in the future?
increased food production per unit area
Increased production of food in the past has depended on ________ and _________.
expanded irrigation, growing use of fertilizer
Goals for genetic engineering of crop species include all of the following except: 1.higher yields. 2.plants with nitrogen-fixing ability. 3.plants that spread freely to any and all open land. 4.plants with greater resistance to heat and drought. 5.plants with greater resistance to cold
3.plants that spread freely to any and all open land
Eating low on the food chain is more efficient than eating high on it. However according to the Environmental Science text, conversion of all present rangeland to crop land would increase environmental damage because:
not all land is suitable for agriculture; some is better suited to grazing
About 11% of the Earth’s surface (excluding Antarctica) is under agriculture. In simple terms, if the world’s human population doubles in the future, then either the total agricultural acreage must double or else __________ must double.
agricultural yields per acre
What is the relationship between farming and ecological succession:
farming keeps the land in an early successional stage
a set of methods to control pest organisms by using natural ecological interactions:
Integrated Pest Management:
considers effects of the pest-control method on the entire ecosystem
Even fertile land not naturally threatened can undergo desertification. Around the world, this has been most widely caused by:
What is the principle drawback of broad-spectrum pesticides?
toxic to beneficial organisms and humans
The type of soil at a particular site depends on many factors. Which of the following is not a factor influencing the soil type? 1.biomagnification. 2.parent material. 3.climate. 4.biological activity. 5.slope
Use of predators, parasites, and competitors for pest control defines what?
biological pest control
The purpose of adding a “terminator gene” to a genetically modified crop species is to prevent:
the crop from producing seeds for the following year
If the current growth rate of Nicaragua is 2% then the doubling time for this country is:
Positive feedback ________ change.
What are among the causes of Indirect deforestation?
Acid rain and Ozone
By 2050, human population is predicted to reach ___ billion.
Many fish contain high lvls of _________.
Black lung disease results from:
Coal dust literally filling lungs like dust in a vacuum cleaner bag.
Nuclear fission occurs when a high-energy particle, a neutron, strikes a uranium atom, releases energy &:
breaks in half, causing another atom to break.
A chain reaction occurs inside a nuclear reactor because:
during each fission reaction, multiple neutrons are released each of which goes on to hit other nuclei, causing them to split and releasing more neutrons.
Natural gas is considered a better fossil fuel than oil:
because burning natural gas is cleaner than burning oil.
Fluxes of Nitrogen both into and out of the atmosphere are controlled in most cases by:
chemical exchange with the oceans.
The most abundant fossil energy source is ______ _______.
Species can be especially vulnerable to extinction when:
the population is small.
Random changes in the frequencies of traits in a population are called
Growth occurs at a constant rate per time period: The doubling time of a population: The doubling time of a population:
is a function of exponentiol growth
Justification that sees some aspect of the environment as valuable because it provides individuals with economic benefits
About 90% of energy consumed in the U.S. today are from nonrenewable fossil fuels: ______ , ______, and ________.
petroleum, natural gas and coal
Human demography suggests that an improving economy in a country correlates with:
decreased birth rate, decreased population growth rate
Which of the following is one reason that many scientists do not consider clean coal technology, such as Coal-To-Liquid (CTL) technology or Integrated Gasification Combined Cycle (IGCC), to be a ‘clean’ choice?
Large quantities of carbon dioxide, the most important greenhouse gas, are produced by ‘clean coal’ technologies.
energy produced from any source other than fossil fuels:
Environmental and/or human health impacts from strip mining include?
Flooding, landscape change and soil erosion
If an environment has a carrying capacity of 1,000 individuals for a given species, and 200 individuals of that species are present, we can predict that the population size will _____.
A train carries 200 passengers from Washington, D.C. to New York. The locomotive uses 2800 liters of diesel fuel during the trip from the 5000 liter tank. Afterward, when the destination was reached, all the energy that was in the diesel burned changed to:
What is geothermal energy?
useful conversion of natural heat from the interior of the Earth