IB Environmental Science
If in a human population of 10 000, there are 200 births per year and 100 deaths per year, the Natural Increase Rate would be
0.01
If the crude birth rate of a country in a particular year is 16 per 1 000, and the crude death rate is 8 per 1 000, what is the annual population growth by natural increase?
0.8%
The main difference between 'S' and 'J' population growth curves is that
'J' curves reach no stable maximum.
The frequency of bush fires increases as the abundance of an inflammable plant species increases. At the same time, the increased frequency of fires leads to a decrease in the population of certain animals. In what way(s) is the fire acting in this example?
As a density-dependent factor for plants and a density-independent factor for animals
Which process involved in the cycling of matter could be described as a transformation process requiring the input of solar radiation?
Conversion of nitrates into organic molecules containing nitrogen
These three pyramids represent the population of three different countries: Which of the following correctly describe the populations of the three countries?
Country 1- rapidly expanding Country 2- stable Country 3- Declining
A population has a Natural Increase Rate of 2.0 %. The crude birth and death rates (per thousand) for this population could be
Crude Birth Rate- 32 Crude Death Rate- 12
Which statement is correct? A. A lake is an example of an isolated system. B. An open system exchanges energy but not matter with its surroundings. C. The most common systems found on Earth are closed systems. D. A closed system exchanges energy but not matter with its surroundings.
D. A closed system exchanges energy but not matter with its surroundings.
Which statement about trophic levels is correct? A. The biomass per unit area usually increases with each trophic level. B. A trophic level defines the feeding rate of an organism in a food chain. C. No organism can occupy more than one trophic level in a food web. D. Naturally occuring terrestrial food chains rarely have more than five trophic levels.
D. Naturally occurring terrestrial food chains rarely have more than five trophic levels.
The data below refer to the world population in 1998. Crude birth rate = 23 per thousand Crude death rate = 9 per thousand The Natural Increase Rate was
1.4
The following data were collected in a study of secondary productivity in a population of woodlice. Some of the woodlice produced offspring during the experiment.Gross productivity (g) of this population over the period of the experiment was
1.71
This question refers to the flow diagram below. is the maximum sustainable yield of timber from this forest?
1.8 kg m-2 yr-1 GPP- R = max. sus. yield
The energy available to the tertiary consumers (top carnivores) in a particular ecosystem is 10 kJ m-2 y-1. How much energy (in kJ m-2 y-1) is likely to be passed on by the producers to the primary consumers?
1000
A population has a crude birth rate of 28 per thousand and a rate of increase of 1.4 %. What is the crude death rate per thousand?
14
If the producer biomass in an ecosystem is 150 kg per hectare (kg ha-1), what is the approximate primary consumer (herbivore) biomass (in kg ha-1) that might be expected in the same ecosystem?
15
The diagram below shows the relative size of some energy flows between four types of organisms in a small pond, over one year. What is the gross productivity of the primary consumers?
15 9+6
In a deer population of 1000, each year an average of 100 die from natural causes and 250 are born. Assuming no immigration or emigration, the sustainable yield is
150
What proportion (by volume) of the Earth's water is fresh?
2.6%
If the producer biomass in an ecosystem is 300 kg ha-1, what is the approximate secondary consumer biomass (kg ha-1) likely to be in the same ecosystem?
3
The amount of water present in the hydrosphere as freshwater is approximately
3%
For a population with a Natural Increase Rate of 2 %, the doubling time in years is
35
The graph below shows human population projections by region. By approximately how many times is the world population in 2125 expected to exceed the population in 1950?
4
In a survey of an antelope population, 80 antelope were marked and released. Two weeks later a second sample was captured, of which 16 antelope were found unmarked and 4 were marked. What would be the estimated population size?
400
If C = 4000 kJ day-1 and SP = 200 kJ day-1, the efficiency of conversion is
5%
An area of forest contains a volume of 1.5 million m3 of timber. On average, each year bushfires destroy 50 000 m3 and pests destroy 100 000 m3 of timber. Normal tree growth adds 200 000 m3. What is the approximate sustainable yield of the forest in m3 yr-1?
50, 000
The percentage of the earth's surface covered by oceans is about
70%
This question refers to the graphs below. Which graph shows the most probable change in the biodiversity (measured as the number of species present per unit area) of an ecosystem undergoing succession?
A
Which of the following is the best definition of a system?
An assemblage of parts, and their relationships, forming a whole
Which is an example of negative feedback?
An increase in a herbivore population, leading to overgrazing and thus to a decline in the herbivore population.
Which is most likely to be an internal density dependent factor regulating a population of herbivores?
An increased fertility rate as herbivores decrease in number
Which of the following is an example of mutualism?
An insect pollinating an orchid flower
Which system represents a herd of elephants living on the African grassland?
An open system
For a particular year, for the fishing grounds of an island nation, assume: R = the biomass of young fish reaching harvestable size G = the growth in biomass of fish already of harvestable size M = the loss of fish through death and emigration B = the biomass of the total fish population at the start of the year. The sustainable yield of the fishing grounds could be calculated using which of the following?
R + G - M
Which of the following can generally be deduced from the shape of the survivorship curves for a given species?
Relative amount of parental care and investment per individual offspring
Why is it difficult to calculate carrying capacities for human populations?
Resources can be imported and exported and the level of technology can influence carrying capacity.
Which of the following correctly represents the energy transformations involved in respiration and photosynthesis?
Respiration- chemical to heat Photosynthesis- Light to chemical
Which of the following factors would prevent the ecosphere being classified as a closed system?
The arrival of rocks as meteorites from space
Which statement describes secondary productivity?
The biomass gained by heterotrophic organisms through feeding and absorption
Which statement best describes the niche of a species in its habitat?
The biotic and abiotic components it requires
Which statement best describes a climax community?
The end-point of ecological succession
Which of the following can be considered an isolated system?
The entire cosmos
Which of the following does not represent an open system?
The entire universe
Which could not be described as natural capital?
The fish harvested from the inshore waters of one country in one year
Which of the following is the best definition of a population?
The number of individuals of the same species in a given area
Which statement most correctly describes K-strategist organisms?
They reach adulthood slowly and have few young
Which of the following is a characteristic of K-selected organisms?
They usually have a high degree of parental care of young.
The downward leaching of nutrients within the soil profile is primarily an example of which of the following?
Transfer of materials
Which row correctly gives examples of transfer and transformation processes?
Transfer- organic matter entering the oceans Transformation- Evaporation
Which list contains only abiotic components of an ecosystem?
air, water, rock
Over a long period of time, energy input to a system is
always equal to energy output.
A system may best be defined as
an assemblage of parts and their relationships forming a whole.
A parasite, infecting the organs of its host, spreads from host to host more rapidly when the host population, in a given area, is higher. Assuming infection with the parasite reduces fertility, this would be an example of control of the host population through
an external, density dependent factor
Which statement about the ozone layer is correct?
Ultraviolet radiation is absorbed during the process of stratospheric ozone formation
Which graph best represents the change in growth rate of an S-shaped population growth curve?
Upside down parabola
Which statement about energy transformations is correct?
When an organism grows its entropy usually decreases.
Which statement best illustrates the second law of thermodynamics?
When chemical energy such as food is converted into mechanical energy such as movement, much energy is lost as heat.
The diagram below shows the flow of energy through a food web. Gross Primary Productivity is
b-c
The diagram below shows the flow of energy through a food web.Gross Primary Productivity (GPP) is
b-c
As succession approaches a climax, which changes are likely to occur in an ecosystem?
Gross productivity of whole ecosystem- Increase Net productivity of whole ecosystem- Decrease Inorganic mineral storages- Decrease
Which process reduces storages of soil nutrients?
Heavy rainfall
Which of the following are found at the second trophic level in a food chain?
Herbivores
The graph below shows the number of individual organisms surviving from an initial cohort of 1000, plotted against time. (A cohort is a group of organisms in a population that are born or hatch at about the same time.) Which line on the graph is most likely to represent a K-strategist?
I
Which population shows clearest evidence of positive feedback during this time?
I
The diagram below represents the flows of energy through the biosphere. Which of the following correctly distinguishes flows I to V as transfer or transformation processes?
I & III- Transfer II, IV, V- Transformation
The main factors that determine the type of biome found are I. temperature. II. precipitation. III. soil type. IV. wind direction.
I and II only
What information is necessary to calculate the net primary productivity of an ecosystem? I. The biomass produced by photosynthesis per unit area per unit time. II. The biomass lost by the plant by respiration per unit area per unit time. III. The biomass gained by heterotrophic organisms per unit area per unit time. IV. The biomass potentially available to consumers per unit area per unit time.
I and II only
Which of the following are examples of mutualism? I. Bacteria fixing nitrogen in the roots of plants II. The pollination relationship between flowering plants and insects III. Lions hunting zebras IV. Mosquitos spreading malaria
I and II only
Which of the following is a transfer process / are transfer processes? I. Deposition of sand by waves on beaches II. Organic matter entering the ocean III. Decomposition of organic matter at the bottom of a lake IV. Run-off of water from land to rivers
I, II and IV only
Which of the following combinations is typical of r-selected organisms? I. A high number of offspring II. A tendency to be associated with temporary habitats III. Completion of the life-cycle in a relatively short period IV. A low number of offspring V. A high level of parental care VI. A rapid rate of growth
I, II, III, and VI only
Ecological succession generally involves I. a decrease in the entropy of an ecosystem. II. loss of communities through competition. III. an increase in the ratio of organic to inorganic storages.
I, II, and III
Sustainable yield can be defined as I. annual growth and recruitment - annual death and emigration. II. (total biomass at time t + 1) - (total biomass at time t). III. the highest rate at which natural capital can be exploited without reducing its original stock.
I, II, and III
Which combination of characteristics is most likely to be associated with a stable or falling human population? I. Increase in the proportion of women receiving higher education II. Increase in average income III. Decrease in the average age of marriage IV. Increase in birth rate V. Decrease in death rate VI. Increase in the average age of marriage
I, II, and VI
Four examples of natural capital are (i) water stored in a stratum of permeable rock; (ii) crude oil stored in an oil-trap in rocks; (iii) a stand of coniferous trees in a 25-year-old plantation; (iv) a seal colony on an Antarctic island. To which of the three broad classes of natural capital (given below) do each belong? R = renewable N = non-renewable Rp = replenishable
I- Rp II- N III- R IV- Rp
A stable ecosystem will be in . . . (I) . . . equilibrium, achieved largely through mechanisms of . . . (II) . . . feedback.
I- Steady State II- Negative
Species associated with pioneer and early sevral communities tend to have ... (i) ... young, which mature ... (ii) ... and are often given ... (iii) ... parental care. Such organisms often have a ... (iv) ... life span. Which of the following provides the correct set of words to be inserted in the above sentence?
I-many II-quickly III-little IV-short
Below is the diagram of the nitrogen cycle. Denitrification is
II
Which of the following stages of the nitrogen cycle is a transfer process/are transfer processes? I. Specialized bacteria converting atmospheric nitrogen to ammonia (NH3) II. Dilute nitric acid (HNO3) falling as rain in a lake III. Run-off of nitrogen fertilizers from land to rivers IV. Decomposition of nitrogen-rich organic compounds into simpler nitrogen-containing inorganic compounds
II and III
The human carrying capacity of a country might be increased by I. increasing literacy rates among women. II. switching electricity production to renewable energy sources. III. an increase in imported resources.
II and III only
As a result of global warming, there could be increased I. snowfall at the poles. II. melting of polar ice caps. III. photosynthesis. Which could produce positive feedback in the Earth's climate system?
II only
Recycling of a non-renewable resource can be of environmental value because it is likely to lead to I. a reduction in use of the resource. II. a reduction in resource exploitation. III. an increase in natural income. IV. an increase in natural capital.
II only
The graphs below show four different population growth curves. Which best represents (i) the total human population; (ii) a bacterial population in a laboratory; (iii) a predator/prey relationship?
III IV II
Which of the following conditions would lead to unsustainable harvesting of timber from a forest? I. Harvesting trees before they are fully mature. II. Regularly harvesting the full natural income from the forest. III. Reducing mineral content of soil through harvesting.
III only
Which statement(s) correctly describe the relative productivity of different biomes? I. The productivity of biomes always decreases with increasing distance from the equator. II. The productivity of biomes is directly proportional to the amount of solar energy they receive. III. The productivity of biomes is related to the prevailing climatic conditions at their latitude.
III only
The following are processes occurring in mineral cycles: I. conversion of carbon dioxide to organic matter II. conversion of phosphates to organic matter III. convection of water vapour IV. conversion of nitrites to nitrates Which of the above processes does not depend directly on input of solar energy?
IV only
Which of the following contains the greatest proportion of the world's fresh water?
Ice-caps and glaciers
Which statement best describes the second law of thermodynamics?
In any isolated system entropy tends to increase spontaneously.
If a tropical river were to be accidentally polluted with a pesticide, where is the highest concentrations of the pollutant most likely to be found after several years?
In crocodiles and other carnivores
If toxic materials were to be released into a coral reef ecosystem, in which part of the ecosystem would you expect them to accumulate to the greatest extent?
In the tissues of large carnivorous fish such as sharks
Which of the following is most likely to lead to an overall increase in the Earth's freshwater storages? A. Removal of forests B. Melting of polar ice caps C. Increase in evaporation rates from the oceans causing increase in precipitation over the continents D. Discovery of new underground aquifers
Increase in evaporation rates from the oceans causing increase in precipitation over the continents
Which of the following possible impacts of global warming would be most likely to slow further increases in mean global temperatures?
Increased evaporation leading to greater snowfall in the polar regions
Which statement best explains why the net productivity of a climax community approaches zero as a result of succession?
Increased length of food chains have led to an increase in respiration.
Which combination of abiotic factors is typical of the tropical forest biome?
Narrow range of temperatures and high rainfall
In which group are there examples of each of a non-renewable, renewable and replenishable resource?
Natural gas, fish, stratospheric ozone
The graph below shows how a population changed over a period of time. Which of the following best describes the regulation process in this system? ---- ------ ----- --- -------- ------------ ------
Negative Feedback
When a population exceeds the carrying capacity of the environment that supports it, which process often restores the equilibrium?
Negative Feedback
Which of the statements about negative feedback is correct?
Negative feedback counteracts deviation from equilibrium in a system.
Which of the following contributes most effectively to self-regulation within a system?
Negative feedback mechannisms
If the rates of photosynthesis and respiration (in a plant) were exactly equal, which of the following would be true?
Net productivity would be zero
Which statement about the storage of nitrogen in ecosystems is correct?
Nitrogen is stored in the animal biomass of an ecosystem mainly in the form of protein
The diagram below shows a complete food web. Each letter represents a species.
O
The diagram below shows a complete food web. Each letter represents a species. Which are producers? n<-----O------->T
O
In which way do "S" and "J" population curves differ from one another?
Only S curves show negative feedback as the population stabilizes.
A desert with very low precipitation and little vegetation is an example of which type of system?
Open
Which row contains correct statements about exchanges between open and closed systems and their surroundings?
Open system- exchanges matter and energy Closed system- exchanges energy but not matter
The diagram below represents the inputs and outputs of water from a lake over a period of time. Assuming there is neither a rise nor a fall in the level of the lake, and there are no other inputs or outputs, what is the value of R?
P+I-E-S
Which of the following correctly lists two of the requirements of photosynthesis and respiration?
Photosynthesis- Carbon dioxide and water Respiration- Organic matter and oxygen
The figure below shows a simplified model of the carbon cycle. Each arrow represents a process which involves a transfer of carbon. What are processes X, Y and Z?
X- combustion Y- Respiration Z- Photosynthesis
These statements describe changes taking place in the populations of two different countries: • Country X begins to import a resource from another country. • Country Y increases its birth rate through a population policy. Which of the following predict the most likely effects these changes will have on the carrying capacity of each country?
X- increase in carrying capacity Y- No change in carrying capacity
The following graphs represent the changes in population density of two species:
X- predator Y- prey
Calculate the missing values in the table.
Y- 1321 Z- -0.5
A biome is
a collection of ecosystems sharing similar climatic conditions
An increase in parasitism, causing reduced survival in a host population as that population increases in size, is an example of
a density dependent factor
Compared to pioneer communities, climax communities usually have
a higher gross productivity
The carrying capacity of an environment for a given species
can only be exceeded with unsustainable use of resources
An input to photosynthesis is
carbon dioxide
In a demographic transition model
changes in birth rate lag behind changes in death rate.
Natural Increase Rate of a human population is
crude birth rate- crude death rate/ 10
Nitrogen is returned to the atmosphere by
denitrifying bacteria.
The net productivity for the consumer community is
e-g-j
Food chains seldom have more than four members because
energy is lost as it moves along a food chain and little remains at the top carnivore level
Inputs to a closed system may be
energy only
The graph below shows the number of pairs of penguins breeding on an island in the Southern Ocean. The graph could be used to
estimate the growth rate of the population
Which is a renewable resource?
fish in the sea
Which list below contains only components of renewable natural capital?
fish, timber, cattle
Net Primary Production is the amount of energy
fixed in an ecosystem by photosynthesis, minus the losses due to respiration by producer organisms
Compared to a pioneer community, a climax community would have
higher gross productivity
Extensive use of recycling might
increase human carrying capacity.
An r-strategist generally
is small and short-lived
The Second Law of Thermodynamics states that in any
isolated system, entropy tends to increase spontaneously
The carrying capacity of a country depends mostly on
its state of economic and technological development.
Which unit is the most appropriate to express the gross primary productivity of an ecosystem?
kg m-2 y-1
The main deserts of the world are found at
latitudes between the temperate and tropical forests
Nitrogen is removed from the atmosphere by
lightning
Modern commercial agricultural practices tend to
lower species diversity in the community. reproduce early stages of succession to maximize net productivity. create conditions favorable for r-selected species. ALL OF THE ABOVE
Net primary productivity is the total biomass
made from inorganic matter that remains after respiratory losses
As disease spreads through a population, numbers fall. As the result of a reduction in contact between individuals, the rate of spread of the disease is reduced. This is followed by a recovery in numbers. This is an example of
negative feedback
A mineral resource, such as aluminium ore, can
never be exploited sustainably.
Below is the diagram of the nitrogen cycle.Which is the most important flow not shown in the diagram?
nitrate ions → plant
A diversity index of an ecosystem typically takes into account
number of species and their abundance
The units used for birth rate and death rate in this model are most likely to be
numbers per thousand individuals per year
The table below shows processes carried out by three different organisms. Which statement is correct?
obtain organic matter from other organisms- Green Plants- No Decompose Organisms- Yes Fish- Yes
A lake with a stream flowing into it, but with water lost only by evaporation, is an example of a system which is
open
Net Primary Productivity (NPP) is the total amount of energy fixed in an ecosystem by
photosynthesis minus the amount used by producers in respiration
Two herbivorous animals are part of the same community. One of them is prey to many predators and the other has no natural predator. They are
primary consumers and occupy different ecological niches
The fact that India has a very high rate of recycling plastics and metals from domestic rubbish (garbage),
reduces India's consumption of non-renewable resources
The ozone layer can be considered as natural capital which is
replenishable and provides an essential service
The largest store of carbon on earth is in
rocks and soils
A community is composed of
several populations
The diagram below represents the pyramid of biomass for a certain ecosystem.The most likely explanation for the biomass of trophic level 2 being greater than that of trophic level 1 is that the
system shows seasonal fluctuations and the plants have died off before the herbivores
It is difficult to estimate accurately the global carrying capacity for the human population because
technological developments may lead to changes in rates of resource consumption.
Major climatic factors affecting ecosystems are
temperature and precipitation
In a normal terrestrial ecosystem, most nutrients
tend to be recycled
Overpopulation occurs when
the available resources cannot support the number of people in the area at a reasonable standard of living
Biomass is best defined as
the dry weight of organic material
"The change in a system's internal energy is equal to the energy absorbed by the system minus the energy released into its surroundings." This statement best illustrates
the first law of thermodynamics
Fertility rate is
the number of births per thousand women of child-bearing age per year.
The capacity of a system to self-regulate is generally increased by
the presence of negative feedback
A ecological niche is
the role a species has in an ecosystem
In the process of succession, earlier communities disappear because
they are displaced through competition
If a lake is sprayed with a non-biodegradable insecticide to kill mosquitoes, after a few years the highest concentrations of insecticide are most likely to be found in the
tissues of predatory fish and fish-eating birds
Leaching of soil nutrients is an example of
transfer of materials
In the diagram below all values are in kJ m-2 yr−1. The values of W, X, Y and Z are
w- 8000 X-7600 Y-80 Z-69 Subtract moving up the chain.
Which list includes three abiotic factors that affect aquatic plants?
water temperature, oxygen concentration, light intensity
An ecological niche is
where a species lives and what it does in its environment
Below is a diagram of a food web. The letters represent different species of organism. S is a photosynthesizing organism. Which organism is only a primary consumer (herbivore)?
T
In a mature forest, the trees are eaten by small primary consumers which are then eaten by much larger secondary consumers. Which of the following pyramids best represent this ecosystem?
Pyramid of numbers- 2:3:1 Pyramid of biomass- 1:2:3
What is a biome?
A collection of ecosystems sharing similar climatic conditions
Which is an example of negative feedback?
A decline in a larger predator population after they have eaten most of their prey population
Which of the following is most likely to be a parasite?
A fungus in the living tissues of a tree
What is a group of organisms of the same species living in the same area at the same time known as?
A population
Which of the following might show primary succession?
A rock surface exposed by a retreating glacier
Below is a diagram of a food web. The letters represent different species of organism. S is a photosynthesizing organism. What is organism U?
A secondary consumer (carnivore)
Which statement relating to trophic levels is true?
A single species may occupy more than two different trophic levels
Which statement expresses the second law of thermodynamics? A. The amount of energy available to do useful work in a system decreases over time. B. Energy can neither be created nor destroyed. C. Entropy will always decrease spontaneously in a system over time. D. Energy inputs equal energy outputs.
A. The amount of energy available to do useful work in a system decreases over time.
Which statement about a food chain is correct?A. The top carnivore is the species most vulnerable to extinction. B. The system is very efficient with low energy loss. C. Approximately 10 % of energy is lost in every transfer. D. The tertiary consumers will always have the largest number of individuals.
A. The top carnivore is the species most vulnerable to extinction.
The graph below shows human population projections by region. The projected populations from year 2000 to 2125 are:
Africa- rising China- rising Developed World- falling Latin America- rising
What does the first law of thermodynamics tell us?
All energy comes from other energy.
An animal population is given 50 kg of feed per day, of which 40 kg is consumed. 20 kg of feed per day is used in respiration and 15 kg of faeces per day is released. Which of the following are the correct values for gross and net productivity?
GPP- 25 NP- 5
Which statement is correct? A. A food chain can never have more than four members. B. Ecosystems that have a high productivity often also show high biodiversity. C. One ecosystem can never contain another within it. D. Pioneer communities usually contain more plant species than climax communities.
B. Ecosystems that have a high productivity often also show high biodiversity
Which of the following contains only transfer processes? A. Melting of ice caps; evaporation of sea water B. Run-off of water from land to rivers; dead organic matter entering a lake C. Formation of water droplets in clouds; volcanic eruptions D. Leaching of soil nutrients; freezing of lake water
B. Run-off of water from land to rivers; dead organic matter entering a lake
Below is a simplified diagram of the nitrogen cycle. Which process transfers nitrogen from the soil to the atmosphere?
Bacterial decomposition of nitrates
Which of the following is an essential feature of a system in steady-state equilibrium?
Balanced inputs and outputs
What information would you need to estimate the gross productivity of a population of consumers over a period of time?
Biomass of food eaten and biomass of feces produced only
Which of the following does not influence human carrying capacity?
Birth rate
The diagram below shows energy transfer in a cow. Secondary Productivity is
C- (R+U+F)
Which statement is correct?A. Secondary consumers can be abiotic or biotic components of ecosystems. B. Temperature, soil pH and decomposers are abiotic components of soil ecosystems. C. Primary consumers are always biotic components of ecosystems. D. Bacteria, turbidity and plankton are biotic components of marine ecosystems.
C. Primary consumers are always biotic components of ecosystems
Which of the following statements about food chains is true?
Carnivores are never at the second trophic level
Which statement is correct?
Elephants are K-strategists because they have a low population growth rate
What do outputs from an open system consist of?
Energy and matter
How is the net productivity of the producers in an ecosystem defined?
Energy fixed by biomass per unit time minus respiratory losses
Which statement describes the result of the first law of thermodynamics?
Energy input always equals energy output
The diagram below shows part of an aquatic food web for a lake ecosystem. What is the maximum number of trophic levels represented in this food web?
Five
The diagram below represents the flows of energy through the biosphere. Which of the following correctly shows the absorption or release of in each of the flows II and V?
Flow II- Absorbs CO2 Flow V- Releases CO2
The diagram below represents the flows of energy through the biosphere. Which units would be most appropriate for flow II and the "chemical energy in plant biomass"?
Flow II- kJm^-2 yr^-1 Chemical energy in plant biomass- kJm^-2
Which row shows how energy and materials move through each type of system?
Isolated system- energy does not leave system Closed system- energy flows through system Open system- materials flow through system
Which of the following descriptions best represents a closed system?
It exchanges energy but not matter
Which of the following is an example of negative feedback?
More carbon dioxide favoring plant growth, so plants absorb more carbon dioxide
Which interaction would benefit both organisms in a relationship?
Mutualism
Which is the best explanation of the advantage of contour-plowing? A. Plowing across the contours improves the efficiency of harvesting techniques. B. Plowing across the contours improves drainage of the soil. C. Plowing parallel with the contours prevents erosion of the soil. D. Plowing parallel with the contours improves drainage of the soil.
Plowing parallel with the contours prevents erosion of the soil.
Which of the following has been most effective in reducing growth rates in human populations?
Policies which increase the economic independence of women
Which of the following populations are most likely to be sustainable?
Population density- high Mean Individual consumption- low High dependence on- renewable resources
Which of the following correctly describes the components of a population, community, ecosystem and habitat?
Population- Biotic only Community- Biotic only Ecosystem- Biotic and abiotic Habitat- Biotic and abiotic
Of what is the diagram below an example? Global warming ----> ice-caps melt -----> less energy reflected ------> increased global temperature --------> global warming
Positive feedback
The accelerating decline in the population of a country in which the average age was increasing, provides an example of which of the following?
Positive feedback
The diagram above is an example of ← less CO2 uptake by oceans← warmer ocean temperature ← warmer atmospheric temperature ← atmospheric CO2 increases
Positive feedback
Which statement best illustrates the second law of thermodynamics?
Potential energy decreases as energy and matter move through a system
Which form of natural capital absorbs carbon dioxide?
Producers
Which organisms have a net output of oxygen?
Producers
Which term could not be applied to an organism feeding on the biomass of a producer?
Secondary consumer
The diagram below shows the main energy flows through an ecosystem. What are the organisms in X?
Secondary consumers
Which is least likely to be an example of mutualism?
Small plants of another species attached to the surface of a tree
This is a demographic transition model: Which stage of the demographic transition model would most clearly represent a period of exponential growth for the population?
Stage II
Consider these statements concerning the flow of energy through ecosystems: Statement 1: The amount of energy that is available to living things decreases as it is transformed and passed along food chains. Statement 2: As energy is transformed along food chains, no energy is destroyed. Which is a correct evaluation of these statements?
Statement 1- Demonstrates the second law of thermodynamics Statement 2- Demonstrates the first law of thermodynamics
How are the flows and storages of matter and energy generally represented in flow diagrams?
Storages- boxes Flows- arrows
This is a demographic transition model: Which of the following most likely represents the stages of demographic transition reached by the given countries:
Sweden- IV Kenya- II India- III USA- IV
Which of the following best describes the result of positive feedback in a system?
The system changing further in the same direction
Which of the following is characteristic of r-selected organisms?
They are typical of pioneer communities