Variety of different species, genetic variability among individuals within each species, variety of ecosystems and functions such as energy flow and matter recycling needed for the survival of species and biological communities.
Source of energy in some decomposers; fermentation. Does not require oxygen.
All organisms that are the same number of energy transfers away from the original source of energy that enters an ecosystem.
Animal that feeds on animal-eating animals.
gross primary productivity
The rate at which an ecosystem's producers capture and store a given amount of chemical energy as biomass in a given length of time.
Group of individual organisms of the same species living in a particular area.
net primary productivity
Rate at which all the plants in an ecosystem produce useful chemical energy; equal to the difference between the rate at which the plants in an ecosystem produce useful chemical energy and the rate at which they use some of that energy.
Organism that feeds only on primary consumers.
Organism that feeds on dead organisms that were killed by other organisms or died naturally.
number of different species and their relative abundance in a given area.
complex metabolic process that occurs in most living cells to release energy. Requires oxygen.
uses solar energy or chemical energy to manufacture the organic compounds it needs as nutrients from materials obtained from the environment.
organism that feeds on all or parts of plants or on other producers
the variety of forests, deserts, grasslands, oceans, streams, lakes, and other biological communities interacting with one another and their nonliving environment
What illustrates exponential growth?
the king who promised to double time the number of grains of wheat he put on each successive square of a checkerboard, human population growth, money in a savings account
What would be considered a very high rate of annual exponential growth?
If the world's population grew by 2% in 1998 and continued at that rate, how long would it take Earth's population to double?
35 years because 70 divided by 2. The rule of 70.
Which of the following generalizations about developing countries is true?
They use about 12% of the world's resources
Which of the following best describes the concept of environmental degradation?
letting agricultural runoff cause oxygen depletion and fish kills downstream
What best illustrates the tragedy of the commons?
a factory pollutes a river as much as the law allows.
Resources that are called nonrenewable
are capable of economic depletion
What is an example of recycling?
collecting and re-melting aluminum beer cans
Point sources of pollution include
an automobile tailpipe, a factory smokestack, a drainpipe from a power plant
Pollution cleanup efforts can be ineffective because
they often transfer pollutants from one part of the environment to another, once pollutants are dispersed it costs to much to reduce them to acceptable levels, and they can be overwhelmed by growth in population and consumption
Root causes of environmental problems include
rapid population growth
Hunter-gatherer environmental impacts were kept low by
giving nature time to recuperate after they moved on
The Agricultural Revolution resulted in
increased soil erosion, increased deforestation, and increased manipulation of nature
The early Industrial Revolution brought
an increased number of assembly-line jobs, an increased number of coal-mining jobs, and accelerated exponential human population growth
What behaviors would be least appreciated by the scientific community?
overstating a claim
is the creation of new products that generally improve the quality of life
Environmental science integrates knowledge from the disciplines of
chemistry and physics, ecology and demography, and economics and politics
Weather forecasters rely on complicated
Human events which affect the environment are generally characterized by
long delays between events and responses
A positive feedback loop is illustrated by
compound interest in a savings account, exponential population growth, the greenhouse effect
What is it called when two people can move an object together but not alone
Protons, neutrons, and electrons are
The volume of an atom is mostly
Isotopes differ from each other by their number of
share electrons between their constituent atoms
Organic compounds include
chlorofluorocarbons, hydrocarbons, and chlorinated hydrocarbons
A parent and child picked up toys one night, the next night the toys were back on the floor. This is an example of
An example of potential energy is
the chemical energy in a candy bar
The relative quality of electricity is
The relative quality of normal sunlight is
Earth is essentially a closed system for
A community of living organisms interacting with one another and the physical and chemical factors of their nonliving environment is called
Characteristics of life forms are
the ability to capture and transform matter and energy from the environment, the ability to reproduce, and the ability to adapt to external change by mutations
Biodiversity emerges from
mutations, natural selection, and extinction
Fossil fuels and minerals are found in the
Life of individual organisms is maintained by
flow of energy and cycling of matter
flows in only one direction
Aquatic life zones are the aquatic equivalent of
What are abiotic factors
light, temperature, and pH
T or F, The existence, abundance, and distribution of a species in an ecosystem are determined by whether the levels of one or more physical or chemical factors fall within the range tolerated by a species
T or F, Organisms can adapt to slowly changing new conditions by acclimation
T or F, Too much or too little of any abiotic factor can limit or prevent growth of a population of a species in an ecosystem even if all other factors are at or near the optimum range of tolerance
T or F, There is no such thing as too much fertilizer
What are factors that have strong effects on terrestrial ecosystems
temperature, precipitation, and nature of the soil
The most inclusive components of the biotic portion of an ecosystem are
producers and consumers
yields glucose and oxygen gas as products
What are examples of consumers?
herbivores, carnivores, and omnivores
An ecosystem can survive without
Most of the energy input in a food chain is
degraded to low-quality heat
Net primary productivity is
usually reported as the energy output of an area of producers over a given time
Humans are most likely to alter the Earth's thermostat through their impact on the compound
The most common gas in the atmosphere is
Nitrogen fixation is accomplished by
Ammonium ions are converted to nitrite ions and nitrate ions through the process of
When nitrogen is added to aquatic systems, it is least likely to result in
immediate decrease in gross primary productivity
When nitrogen is added to aquatic systems, it is more likely to result in
depletion of oxygen in the water, stimulated algae growth, and fish kills.
The major plant nutrient most likely to be a limiting factor is
Phosphorous is used in the composition of
fats in cell membranes, DNA molecules, bones and teeth
What elements are involved in major biogeochemical cycles
nitrogen, sulfur, and oxygen
What best describes biologists' current hypothesis about the production of the earth's atmospheric oxygen?
Photosynthesis by cyanobacteria produced atmospheric oxygen
The most likely sequence for the biological evolution of life is
anaerobic prokaryotes-photosynthetic prokaryotes-aerobic prokaryotes-eukaryotes-multicellular organisms
The fossil record is incomplete because
not all fossils have been found, some fossils have decomposed, and some life forms left no fossils
A change in the genetic composition of a population over successive generations is called
The term used to describe the long-term, large scale evolutionary changes among groups of species is
A gene pool is
the genetic composition of a population
The changes in coloration within the population of peppered moths is an example of
Coevolution can involve the interaction of
plants and herbivores, pollinators and flowers, and parasites and hosts
An ecological niche includes
the nutrient relationships with other species, the types of resource requirements, the range of tolerance to different physical and chemical conditions
Geographic isolation may result from
a volcanic eruption, an earthquake, a mountain range
Biodiversity is believed to be the result of
speciation and extinction
The 2 most important factors in climate are
temperature and precipitation
The term upwelling refers to the movement of
cool nutrient-rich water from the bottom to the surface
During an El Nino-Southern Oscillation
upwellings of cold, nutrient-rich water are suppressed
What are examples of greenhouse gases
carbon dioxide, water vapor, methane
The rain shadow effect refers to
drier conditions on the leeward side of mountain ranges
The most important factor in determining which biome is found in a particular area is
Large ecological regions with characteristic types of natural, undisturbed ecological communities are called
Generally, the limiting factor that controls the vegetative character of a biome is
An explorer seeking the driest place on Earth should begin looking in a
If you were exploring a desert ecosystem, what species would you least expect to find
A tropical grassland with scattered shrubs and stunted trees would be called a
Arctic tundra is perhaps Earth's most fragile biome because of
low rate of decomposition, shallow soil, and slow growth rate of plants
Humans affect grasslands by
planting crops, grazing domestic herds, and drilling wells for water
In a chaparral, you are least likely to find
epiphytes and a dense understory
Trees of the tropical rainforest are most likely to have leaves that are
broadleaf and evergreen
In a tropical rainforest, you would expect to find relatively open space free of vegetation
on the forest floor
Most of the nutrients in the tropical rain forests are found in the
What threatens the survival of coral reefs
increased ultraviolet light from stratospheric ozone depletion, eroded soil from deforestation and poor land management, chemical pollution
Swordfish are classified as a member of the
What are examples of organisms that are a part of the benthos
lobster, oysters, and sand worms
Populations of organisms living in aquatic life zones may be limited by
access to light, nutrient availability, and dissolved oxygen
The ecosystems with the world's highest net primary productivities per unit area are found in the
Estuaries and coastal wetlands are important because
they are spawning and nursery grounds for marine fish and shellfish, filter out waterbourne pollutants from swimming and wildlife areas, and are breeding grounds for waterfowl
Mangrove swamps serve as
erosion protection for the coastline, prevention of typhoon and hurricane damage, entrapment of sediment washed off the land
The tropical rain forest is to land environment as ____ is to water environments
the coral reef
Over half of the area of estuaries and coastal wetlands in the US has been destroyed or damaged by
sewage runoff, filling, and pesticide and heavy metal pollution
Most photosynthesis in the open sea occurs in the
In lakes, large numbers of decomposers are found in the
In lakes, the open-water surface layer is called the
Lakes that have few minerals and low productivity are referred to as
A temperate lake is most likely to show thermal stratification and restriction on mixing of surface and deeper waters during the
An ecologist would expect to find a thermocline in a temperate lake in
summer and winter
Inland wetlands are valuable for
recharging groundwater supplies, recreation, biogeochemical cycling of carbon, nitrogen, and sulfur
Most of the wetlands that are lost are used for
Ecosystem structures are likely to include
species abundance, species diversity, and physical appearance
Ecosystem structure is least likely to include
biochemical reactions in the intestines of detritus feeders
Where is most of the world's biodiversity?
You would predict that large islands near the mainland would have relatively
high immigration and low extinction rates
The best description of a cockroach's niche is
An organism is classified as a specialist or generalist based on
its range of tolerance, its niche, its limiting factors
Species that normally live and thrive in a particular ecosytem are known as
Species that migrate or are accidentally introduced into an ecosystem are called
Birds and trout make good
Which predators avoid competition by being active at different times?
hawks and owls
interspecific competition can be avoided by
eating at different times, resource partitioning, character displacement
A relationship in which a member of one species obtains its nourishment by living on, in, or near a member of anothe species over an extended time is best labeled
What relationship is most likely to be described as a positive feedback loop
The relationship between clownfish and sea anemones is
The win-win relationship of animal behavior is
T or F primary succession is initiated by pioneer species and it often involves species changing the environment so that they can no longer thrive and must be replaced by other species. Also it generally results in more comlex, more self-sustaining stages than the preceding ones.
T or F primary succession is an orderly progression from pioneer species to climax species indicative of the region being studied
What exhibits primary succession?
rock exposed by a retreating glacier
What would undergo secondary succession?
a heavily polluted stream that has been cleaned up
What are the immediate effects of a natural disturbance
changing conditions and releasing resources
Changes such as drought and earthquake are considered to be
natural and catastrophic
What refers to the ability of an organism to return to its former condition after a period of stress?
The changes in population size, density, dispersion, and age structure are known as
The most common pattern of population dispersion found in nature is
The biotic potential of a population
is the maximum reproductive rate of a population
Environment resistance is enhanced by
a specialized niche
What factor leads to an increase in biotic potential?
optimal level of critical nutrients
Carrying capacity refers to
the max. size of population the environment will support
A logistic growth curve depicting a population that is limited by a definite carrying capactiy is shaped like the letter
An exponential growth curve depicting an ever-growing population is shaped like the letter
A population crash occurs when
a population overshoots carrying capacity and environmental pressures cause effects
Density-dependent population controls include
disease, parasitism, and competition for resources
Density-independent population controls include
drought, fire, and unfavorable chemical changes in the environment
What are general types of population change curves
stable, cyclic, irruptive
Wolves controling deer populations are an example of
top-down population control
An r-strategist generally
is small and short lived
are generally less adaptable to change than r-strategists
What best describes the survivorship curve you would expect to find for a fish
Which species is least vulnerable to habitat fragmentation?
What is an example of a r-strategist?