transformed
protected
made uses of
adapted to
Early Lifeforms and Earth's Atmosphere
Why has life flourished on Earth This question has a twopan answer First Earth has been a cradle for life because of its position relative to the Sun Second once life began on Earth simple early lifeforms (photosynthetic bacteria) slowly but inexorably altered the environment in a manner that not only maintained life but also paved the way for later complex lifeforms These changes allowed later organisms to evolve and thrive Humans and other higher organisms owe their lifesupporting environment to these early lifeforms
Earth’s earliest atmosphere contained several gases hydrogen water vapor ammonia nitrogen methane and carbon dioxide but no oxygen Gas mixtures emitted from presentday volcanoes resemble this early atmosphere suggesting its origin from volcanic eruptions in Earth's earliest atmosphere methane and cartoon dioxide occurred at much higher levels than at present—a circumstance that was favorable for early life Methane and carbon dioxide are greenhouse gases that warm atmospheres by retarding loss of heat to space These two gases kept Earth warm during the Sun's early history when the Sun did not bum as brightly as it now does (An early dim period with later brightening is norms for stars of our Sun's type)
Earth's modem atmosphere which is 78 percent nitrogen gas 21 percent oxygen and
2 Paragraph 1 supports which of the following inferences
After complex life forms arose on Earth bacteria quickly evolved in order to maintain favorable conditions for life
Early life forms on Earth arose from the process of photosynthesis
The development of complex life on Earth depended on the presence of bacteria that could be consumed by larger organisms
Complex life forms on Earth may not have evoked if Earth had been farther from or closer to the Sun
Paragraph 1 is marked with an arrow [ ]
Early Lifeforms and Earth's Atmosphere
Why has life flourished on Earth This question has a twopan answer First Earth has been a cradle for life because of its position relative to the Sun Second once life began on Earth simple early lifeforms (photosynthetic bacteria) slowly but inexorably alteredthe environment in a manner that not only maintained life but also paved the way for later complex lifeforms These changes allowed later organisms to evolve and thrive Humans and other higher organisms owe their lifesupporting environment to these early lifeforms
Earth’s earliest atmosphere contained several gases hydrogen water vapor ammonia nitrogen methane and carbon dioxide but no oxygen Gas mixtures emitted from presentday volcanoes resemble this early atmosphere suggesting its origin from volcanic eruptions in Earth's earliest atmosphere methane and cartoon dioxide occurred at much higher levels than at present—a circumstance that was favorable for early life Methane and carbon dioxide are greenhouse gases that warm atmospheres by retarding loss of heat to space These two gases kept Earth warm during the Sun's early history when the Sun did not bum as brightly as it now does (An early dim period with later brightening is norms for stars of our Sun's type)
Earth's modem atmosphere which is 78 percent nitrogen gas 21 percent oxygen and
3 The word emitted’ in the passage is closest in meaning to
Disappearing
examined
Inreleased
taken
Earth’s earliest atmosphere contained several gases hydrogen water vapor ammonia nitrogen methane and carbon dioxide but no oxygen Gas mixturesemitted from presentday volcanoes resemble this early atmosphere suggesting its origin from volcanic eruptions in Earth's earliest atmosphere methane and cartoon dioxide occurred at much higher levels than at present—a circumstance that was favorable for early life Methane and carbon dioxide are greenhouse gases that warm atmospheres by retarding loss of heat to space These two gases kept Earth warm during the Sun's early history when the Sun did not bum as brightly as it now does (An early dim period with later brightening is norms for stars of our Sun's type)
4 The word retarding’ in the passage is closest in meaning to
regulating
slowing
restoring
directing
Earth’s earliest atmosphere contained several gases hydrogen water vapor ammonia nitrogen methane and carbon dioxide but no oxygen Gas mixtures emitted from presentday volcanoes resemble this early atmosphere suggesting its origin from volcanic eruptions in Earth's earliest atmosphere methane and cartoon dioxide occurred at much higher levels than at present—a circumstance that was favorable for early life Methane and carbon dioxide are greenhouse gases that warm atmospheres by retarding loss of heat to space These two gases kept Earth warm during the Sun's early history when the Sun did not bum as brightly as it now does (An early dim period with later brightening is norms for stars of our Sun's type)
5 In paragraph 2 why does the author provide the information that methane and carbon dioxide kept the Earth warm during the Sun's early history
To explain how the early Earth and the early Sun were related
To support the claim that methane and carbon dioxide are greenhouse gases
To explain why the high levels of methane and carbon dioxide in Earth's early atmosphere were favorable for early life
To suggest that these gases affect how brightlythe Sun bums
Paragraph 2 is marked with an arrow [ ]
Earth’s earliest atmosphere contained several gases hydrogen water vapor ammonia nitrogen methane and carbon dioxide but no oxygen Gas mixtures emitted from presentday volcanoes resemble this early atmosphere suggesting its origin from volcanic eruptions in Earth's earliest atmosphere methane and cartoon dioxide occurred at much higher levels than at present—a circumstance that was favorable for early life Methane and carbon dioxide are greenhouse gases that warm atmospheres by retarding loss of heat to space These two gases kept Earth warm during the Sun's early history when the Sun did not bum as brightly as it now does (An early dim period with later brightening is norms for stars of our Sun's type)
6 Paragraph 2 supports which of the following statements about methane and carbon dioxide present in Earth's earliest atmosphere
They slowed down the loss of heat from Earth's atmosphere
They caused the sunlight to be less bright than it currently is
They occurred in smaller amounts than they currently do
They prevented the development of early lifeforms
Paragraph 2 is marked with an arrow [ ]
Earth’s earliest atmosphere contained several gases hydrogen water vapor ammonia nitrogen methane and carbon dioxide but no oxygen Gas mixtures emitted from presentday volcanoes resemble this early atmosphere suggesting its origin from volcanic eruptions in Earth's earliest atmosphere methane and cartoon dioxide occurred at much higher levels than at present—a circumstance that was favorable for early life Methane and carbon dioxide are greenhouse gases that warm atmospheres by retarding loss of heat to space These two gases kept Earth warm during the Sun's early history when the Sun did not bum as brightly as it now does (An early dim period with later brightening is norms for stars of our Sun's type)
7 The word abundant’ in the passage is closest in meaning to
pure
balanced
plentiful
warm
Earth's modem atmosphere which is 78 percent nitrogen gas 21 percent oxygen and about 1 percent argon water vapor ozone and carbon dioxide differs dramatically from the earliest atmosphere just described The modem atmosphere supports many forms of complex life that would not have been able to exist in Earth's first atmosphere because the oxygen level was too low Also if atmospheric methane and carbon dioxide were as abundant now as they were in Earth's earliest atmosphere the planers temperature would like to be too hot for most species living today How and when did the atmosphere change
8 According to paragraphs 2 and 3 which of the following is one way in which Earth's early atmosphere differed from its current atmosphere
it had fewer greenhouse gases
It was warmer
it had lower levels of cartoon dioxide
It did not contain methane
Paragraphs 2 and 3 are marked with arrows [ ]
Earth’s earliest atmosphere contained several gases hydrogen water vapor ammonia nitrogen methane and carbon dioxide but no oxygen Gas mixtures emitted from presentday volcanoes resemble this early atmosphere suggesting its origin from volcanic eruptions in Earth's earliest atmosphere methane and cartoon dioxide occurred at much higher levels than at present—a circumstance that was favorable for early life Methane and carbon dioxide are greenhouse gases that warm atmospheres by retarding loss of heat to space These two gases kept Earth warm during the Sun's early history when the Sun did not bum as brightly as it now does (An early dim period with later brightening is norms for stars of our Sun's type)
Earth's modem atmosphere which is 78 percent nitrogen gas 21 percent oxygen and about 1 percent argon water vapor ozone and carbon dioxide differs dramatically from the earliest atmosphere just described The modem atmosphere supports many forms of complex life that would not have been able to exist in Earth's first atmosphere because the oxygen level was too low Also if atmospheric methane and carbon dioxide were as abundant now as they were in Earth's earliest atmosphere the planers temperature would like to be too hot for most species living today How and when did the atmosphere change
9 The word sustain’ in the passage is closest in meaning to
change
generates
destroy
support
The answer to this riddle lies in the metabolic activity of early photosynthetic lifeforms that slowly but surely transformed the chemical composition of Earth's atmosphere Some of these early organisms were photosynthetic relatives of modern cyanobacteria (bluegreen bacteria) In the process of photosynthesis carbon dioxide gas combined with water yields oxygen In Earth's early days an over the planet countless photosynthetic bacteriaperformed photosynthetic Together these ancient bacteria removed massive amounts of carbon dioxide from Earth's atmosphere by converting it to solid organic carbon These ancient bacteria also released huge quantities of oxygen into the atmosphere Other ancient bacteria consumed methane greatly reducing its amount in the atmosphere When our Sun later became hotter the continued removal of atmospheric carbon dioxide and methane by early bacteria kept Earth's climate from becoming too hot to sustain life Modern cyanobacteria still provide these valuable services today
10 According to paragraph 4 ancient bacteria changed the chemical composition of Earth's atmosphere by performing all of the following activities EXCEPT
raising the temperature of the atmosphere
removing methane and carbon dioxide
creating organic carbon
producing oxygen
Paragraph 4 is marked with an arrow [ ]
The answer to this riddle lies in the metabolic activity of early photosynthetic lifeforms that slowly but surely transformed the chemical composition of Earth's atmosphere Some of these early organisms were photosynthetic relatives of modern cyanobacteria (bluegreen bacteria) In the process of photosynthesis carbon dioxide gas combined with water yields oxygen In Earth's early days an over the planet countless photosynthetic bacteria performed photosynthetic Together these ancient bacteria removed massive amounts of carbon dioxide from Earth's atmosphere by converting it to solid organic carbon These ancient bacteria also released huge quantities of oxygen into the atmosphere Other ancient bacteria consumed methane greatly reducing its amount in the atmosphere When our Sun later became hotter the continued removal of atmospheric carbon dioxide and methane by early bacteria kept Earth's climate from becoming too hot to sustain life Modern cyanobacteria still provide these valuable services today
11 It can be inferred from paragraph 5 that early lifeforms on Earth wereconfined to the oceans because
thick ozone layer at the tome would have made it difficult for
them to survive on land
water was the only available protection they had against
ultraviolet radiation
land provided them with only limited amounts of water
needed for survival
their metabolic systems were inefficient
Paragraph 5 is marked with an arrow [ ]
The bacteria oxygen release improved conditions for life in two ways First oxygen is essential for the metabolic process known as cell respiration that allow cells to efficiently harvest energy from organic food Second oxygen in the upper atmosphere reacts to form a protective shield of ozone Earth is constantly bombarded by harmful ultraviolet (UV) radiation from the Sun Today Earth's upperatmosphere ozone shield absorbs enough UV to allow diverse forms of life to survive But because early Earth lacked oxygen in its atmosphere it also lacked a protective ozone barrier As a result early life on Earth was confined to the oceans where the water absorbed the UV radiation Only after oxygen released by ancient bacteria drifted up into the upper atmosphere and reacted with other oxygen molecules to form a protective layer of ozone could life flourish at the surface and on the land The absence of an oxygen atmosphere on Mars and other planets in our solar system means that these planets also lack an ozone shield that would protect surfacedwelling life from UV radiationThe surface of Mars is bombarded with deadly radiation if any life exists on Mars it would almost certainly be subterranean
12 Which of the sentences below best expresses the essential information in the highlighted sentence in the passage Incorrect choices change the meaning in important ways or leave out essential information
Any life forms that may have existed on other planets probably
were destroyed by UV radiation
Other planets in our solar system lack the oxygen atmosphere
may helps explain why life exists on Earth
The absence of oxygen on other planets means that those planets lack an ozone shield to protect life forms against UV radiation
Life forms cannot survive UV radiation without the protection of an ozone shield
The bacteria oxygen release improved conditions for life in two ways First oxygen is essential for the metabolic process known as cell respiration that allow cells to efficiently harvest energy from organic food Second oxygen in the upper atmosphere reacts to form a protective shield of ozone Earth is constantly bombarded by harmful ultraviolet (UV) radiation from the Sun Today Earth's upperatmosphere ozone shield absorbs enough UV to allow diverse forms of life to survive But because early Earth lacked oxygen in its atmosphere it also lacked a protective ozone barrier As a result early life on Earth was confined to the oceans where the water absorbed the UV radiation Only after oxygen released by ancient bacteria drifted up into the upper atmosphere and reacted with other oxygen molecules to form a protective layer of ozone could life flourish at the surface and on the land The absence of an oxygen atmosphere on Mars and other planets in our solar system means that these planets also lack an ozone shield that would protect surfacedwelling life from UV radiation The surface of Mars is bombarded with deadly radiation if any life exists on Mars it would almost certainly be subterranean
13 Look at the four squares { } that indicate where the following sentence could be added to the passage
But protection against what
Where would the sentence best fit
Click on a square{ } to add thesentence to the passage
The bacteria oxygen release improved conditions for life in two ways First oxygen is essential for the metabolic process known as cell respiration that allow cells to efficiently harvest energy from organic food Second oxygen in the upper atmosphere reacts to form a protective shield of ozone Earth is constantly bombarded by harmful ultraviolet (UV) radiation from the Sun Today Earth's upperatmosphere ozone shield absorbs enough UV to allow diverse forms of life to surviveBut because early Earth lacked oxygen in its atmosphere it also lacked a protective ozone barrier As a result early life on Earth was confined to the oceans where the water absorbed the UV radiation Only after oxygen released by ancient bacteria drifted up into the upper atmosphere and reacted with other oxygen molecules to form a protective layer of ozone could life flourish at the surface and on the land The absence of an oxygen atmosphere on Mars and other planets in our solar system means that these planets also lack an ozone shield that would protect surfacedwelling life from UV radiation The surface of Mars is bombarded with deadly radiation if any life exists on Mars it would almost certainly be subterranean
14 Directions An introductory sentence for a brief summary of the passage is provided below Complete the summary by selecting the THREE answer choices that express me most important ideas m the passage Some sentences do not belong in the summary because they express ideas mat are not presented in me passage or are minor ideas in the passage This question is worth 2 points
Drag your choices to the spaces where they belong To review me passage click on view Text
Earths earliest atmosphere was transformed in ways that allowed the development of complex life forms
Answer Choice
Volcanoes changed Earth's earliest atmosphere in ways mat allowed life to develop and bacteria that used oxygen produced by photosynthesis further altered me atmosphere to what we find today
When the sun became brighter early bacteria removed methane and carbon dioxide from me atmosphere preventing Earth from becoming too hot for He to survive
Early bacteria provided the oxygen that was needed to support the metabolism of complex life forms and to form an ozone shield against deadly UV venation
Volcanic carbon dioxide in Earthwarm enough for life begin during the time when the Sun was too dim to provide much warmth
Earth has been awe to support life because its position relative to me Sun provided it with enough neat but not too much heat for early bacteria to evolve
Complex we evolved on me Earth’s surface but not on Mars or other planets in the solar system because on those plains early surface life was killed by UV radiation
15 The word monumental’ in the passage is closest in meaning to
innovative
surprising
complex
enormous
The Origins of Plant and Animal Domestication
The emergence of plant and animal domestication represented a monumental change in the ways that humans interacted with Earth's resources the rate at which Earth's surface was modified and the rates of human population growth The development of agriculture was accompanied by fundamental changes in the organization of human society disparities in wealth hierarchies of power and urbanization
16 According to paragraph 2 phrases such as 'plant and animal domestication’ and the invention of agriculture’ encourage which of the following wrong ideas
Early farmers were fairly advanced in their knowledge of plants and animals
Agriculture and animal domestication arose as a result of systematic study and experimentation
The change from hunting and gathering to farming and raising animus occurred
Early efforts to raise and animals were generally successful
Paragraph 2 is marked with an arrow [ ]
Phrases like 'plant and animal domestication’ and 'the invention of agriculture’ create the impression that humans made the transition to cultivating plants and tending animals rather abruptly maybe with a flash of insight Most scholars don't think so It seems more likely that humans used and manipulated wild plants and animals for many hundreds of thousands of years The transition to gardens fields and pastures was probably gradual the natural outgrowth of a long familiarity with the environmental requirements growth cycles and reproductive mechanisms of whatever plants and animals humans liked to eat ride or wear
17 The word manipulated’ in the passage is closest in meaning to
observed
consumed
skillfully used
protected
Phrases like 'plant and animal domestication’ and 'the invention of agriculture’ create the impression that humans made the transition to cultivating plants and tending animals rather abruptly maybe with a flash of insight Most scholars don't think so It seems more likely that humans used and manipulated wild plants and animals for many hundreds of thousands of years The transition to gardens fields and pastures was probably gradual the natural outgrowth of a long familiarity with the environmental requirements growth cycles and reproductive mechanisms of whatever plants and animals humans liked to eat ride or wear
18 Which of the sentences below best expresses the essential information in the highlighted sentence in the passageIncorrect choices change the meaning in important ways or leave out essential information
The change to land cultivation was a slow process becausehumans were familiar with the needs of relatively few plants and animals
The cultivation of land occurred gradually as it was the product of extensive human experience plants and animals of value to humans
Gardens fields and pastures were outgrowths of the desire for plants and animals that humans knew from long familiarity were good to eat wear or ride
People learned about environmental requirements growth cycles and reproductive mechanisms through their long familiarity with plants and animals that they liked to eat ride and wear
Phrases like 'plant and animal domestication’ and 'the invention of agriculture’ create the impression that humans made the transition to cultivating plants and tending animals rather abruptly maybe with a flash of insight Most scholars don't think so It seems more likely that humans used and manipulated wild plants and animals for many hundreds of thousands of years The transition to gardens fields and pastures was probably gradual the natural outgrowth of a long familiarity with the environmental requirements growth cycles and reproductive mechanisms of whatever plants and animals humans liked to eat ride or wear
19 What do genetic studies suggest about the theory that 'cultivation and animal domestication were invented in one or two locations on Earth and then diffused from those centers of innovation’
The theory underestimates the speed at which cultivation and animal domestication were diffused
The theory underestimates the number of locations in which cultivation and animal
The theory overemphasizes the importance of selective breeding in cultivation and animal domestication
The theory overemphasizes the importance of cultivation and animals domestication to some groups of people
For years scholars argued that the practices of cultivation and animal domestication were invented in one or two locations on Earth and then diffused from those centers of innovation Genetic studies are now showing that many different groups of people in many different places around the globe learned independently to create especially useful plants and animals though selective breedingProbably both independent invention and diffusion played a role in agricultural innovation Sometimes the ideas of domestication and cultivation were relayed to new places In other cases the farmers or herders themselves moved into new zones taking agriculture or improvements such as new tools or new methods or new plants and animals with them
20 According to paragraph 4 what advantages did the diet of huntergatherers probably have over an early agricultural diet
It required less effort for them to acquire food that was nutritious
It allowed their populations to expand across wider areas
It provided a greater variety of foods needed for them to stay healthy
It allowed them to have more children
Paragraph 4 is marked with an arrow [ ]
Scholars used to assume that people turned to cultivating instead of gathering their food either because they had to in order to feed burgeoning populations or because agriculture providedsuch obviously better nutrition It now seems that neither of these explanations is valid First of all the risk attached to exploring new food sources when there were already too many mouths to feed would be too great Second agriculture did not necessarily improve nutrition or supplies of food A varied diet based on gathered (and occasionally hunted) food probably provided a wider more secure range of nutrients than an early agriculturally based diet of only one or two cultivatedcrops More likely populations expanded after agricultural successes and not before
21 According to paragraph 4 what was the most likely relationship between population growth and food cultivation
Population growth encouraged the development of food cultivation
Population growth was dependent on the development of a varied diet of cultivated foods
Successful methods of food cultivation were developed before population growth occurred
Food cultivation was more successful in situations where population growth was limited
Paragraph 4 is marked with an arrow [ ]
Scholars used to assume that people turned to cultivating instead of gathering their food either because they had to in order to feed burgeoning populations or because agriculture providedsuch obviously better nutrition It now seems that neither of these explanations is valid First of all the risk attached to exploring new food sources when there were already too many mouths to feed would be too great Second agriculture did not necessarily improve nutrition or supplies of food A varied diet based on gathered (and occasionally hunted) food probably provided a wider more secure range of nutrients than an early agriculturally based diet of only one or two cultivatedcrops More likely populations expanded after agricultural successes and not before
22 The word pursue’ in the passage is closest in meaning to
practice
encourage
prefer
combine
Richard MacNeish an archaeologist who studied plant domestication in Mexico and Central America suggested that the chance to trade was at the heart of agricultural origins worldwide Many the known locations of agricultural innovation lie near early trade centers People in such places would have had at least two reasons to pursue cultivation and animal raising they wouldhave had access to new information plants and animals brought in by traders and they would have had a need for something to trade with the people passing through Perhaps then agriculture was at first just a profitable hobby for hunters and gatherers that eventually because of market demand grew into the primary source of sustenance Trade in agricultural products may also have been a hobby that led to trouble
23 Which of the following most accurately reflects MacNeish’s views discussed in paragraph 5 on efforts to cultivate plants and animals
The efforts often failed because huntergatherers had limited access to new information about plants and animals
The efforts were begun out of a desire to produce goods for trade rather than to increase their growers' food supplies
The efforts were sometimes abandoned so huntergatherers could become involved in the more profitable activity of trading
The efforts were not profitable until people began trading food that they had raised for other goods
Paragraph 4 is marked with an arrow [ ]
Richard MacNeish an archaeologist who studied plant domestication in Mexico and Central America suggested that the chance to trade was at the heart of agricultural origins worldwide Many of the known locations of agricultural innovation lie near early trade centers People in such places would have had at least two reasons to pursue cultivation and animal raising they wouldhave had access to new information plants and animals brought in by traders and they would have had a need for something to trade with the people passing through Perhaps then agriculture was at first just a profitable hobby for hunters and gatherers that eventually because of market demand grew into the primary source of sustenance Trade in agricultural products may also have been a hobby that led to trouble
24 Which of the following most accurately describes the relationship between paragraph 6 and a topic discussed in paragraph 5
Paragraph 6 discusses a series of events that calls into question the theory that plants and animals were raised for purposes of trade
Paragraph 6 presents evidence supporting the claim that many sites of agricultural Innovation were located near trade centers
Paragraph 6 identifies problems that led to the raising of plants and animate as the primary source of sustenance
Paragraph 6 traces negative developments that arose possibly as a result of raising plants and animals for trade
Paragraph 5 and 6 are marked with an arrow [ ]
Richard MacNeish an archaeologist who studied plant domestication in Mexico and Central America suggested that the chance to trade was at the heart of agricultural origins worldwide Many of the known locations of agricultural innovation lie near early trade centers People in such places would have had at least two reasons to pursue cultivation and animal raising they wouldhave had access to new information plants and animals brought in by traders and they would have had a need for something to trade with the people passing through Perhaps then agriculture was at first just a profitable hobby for hunters and gatherers that eventually because of market demand grew into the primary source of sustenance Trade in agricultural products may also have been a hobby that led to trouble
EN Anderson voting about the beginnings of agriculture in China suggests that agricultural production for trade may havebeen the impetus for several global situations now regarded as problems rapid population growth social inequalities environmental degradation and famine Briefly explained his theory suggests that groups turned to raising animals and plants in order to reap the profits of trading them As more labor was needed to supply the trade humans produced more children As populations expanded more resources were put into producing food for subsistence and for trade Gradually hunting and gathering technology was abandoned as populations with their demands for space destroyed natural habitats Meanwhile a minority elite emerged when the wealth provided by trade did not accrue equally to everyone Yet another problem was that a drought or other natural disaster could wipe out an entire harvest thus as ever larger populations depended solely on agriculture famine became more common
25 According to paragraph 6 EN Anderson believes that all of the following were consequences of agricultural production for trade EXCEPT
population growth resulting from the need for more labor
harm to natural environments
the uneven distribution of wealth
conflict over resources needed to produce food
Paragraph 6 is marked with an arrow [ ]
EN Anderson voting about the beginnings of agriculture in China suggests that agricultural production for trade may havebeen the impetus for several global situations now regarded as problems rapid population growth social inequalities environmental degradation and famine Briefly explained his theory suggests that groups turned to raising animals and plants in order to reap the profits of trading them As more labor was needed to supply the trade humans produced more children As populations expanded more resources were put into producing food for subsistence and for trade Gradually hunting and gathering technology was abandoned as populations with their demands for space destroyed natural habitats Meanwhile a minority elite emerged when the wealth provided by trade did not accrue equally to everyone Yet another problem was that a drought or other natural disaster could wipe out an entire harvest thus as ever larger populations depended solely on agriculture famine became more common
26 The word subsistence’ in the passage is closest in meaning to
¡ profit
surplus
enjoyment
survival
EN Anderson voting about the beginnings of agriculture in China suggests that agricultural production for trade may havebeen the impetus for several global situations now regarded as problems rapid population growth social inequalities environmental degradation and famine Briefly explained his theory suggests that groups turned to raising animals and plants in order to reap the profits of trading them As more labor was needed to supply the trade humans produced more children As populations expanded more resources were put into producing food for subsistence and for trade Gradually hunting and gathering technology was abandoned as populations with their demands for space destroyed natural habitats Meanwhile a minority elite emerged when the wealth provided by trade did not accrue equally to everyone Yet another problem was that a drought or other natural disaster could wipe out an entire harvest thus as ever larger populations depended solely on agriculture famine became more common
27 Look at the four squares{ } that indicate where the following sentence could be added to the passage
Among the many places that are now known to be centers of independent domestication are Mesopotamia Central China and Mesoamerica
Where would the sentence best fit
Click on a square{ } to add thesentence to the passage
For years scholars argued that the practices of cultivation and animal domestication were invented in one or two locations on Earth and then diffused from those centers of innovation Genetic studies are now showing that many different groups of people in many different places around the globe learned independently to create especially useful plants and animals though selective breedingProbably both independent invention and diffusion played a role in agricultural innovationSometimes the ideas of domestication and cultivation were relayed to new places In other cases the farmers or herders themselves moved into new zones taking agriculture or improvements such as new tools or new methods or new plants and animals with them
28 Directions An introductory sentence for a brief summary of the passage is provided below Complete the summary by selecting the THREE answer choices that express me most important ideas m the passage Some sentences do not belong in the summary because they express ideas mat are not presented in me passage or are minor ideas in the passage This question is worth 2 points
Drag your choices to the spaces where they belong To review the passage click on View Text
Agricultural Invention and animal domestication caused lasting changes to how humans live and to the physical surface of Earth
1
2
3
Answer Choices
The transition from hunting and gathering to raising plants and animals was gradual and led to significant changes in the organization or human societies
Scholars now believe that agriculture and animal domestication began independently in many separate locations and men spread to new areas As trade in agricultural products grew and social inequalities arose new crops were developed specifically to feed the labor needed to support societies
Although it is now dear that agriculture developed independently in many places often the most efficient techniques arose by combining practices of different cultures
Agriculture became more widespread when human populations realized mat an agricultural diet supplemented through trade could provide as much nutrition as the huntergatherer diet
The earliest reason for raising plants and animals may have been to provide goods for trade and such trade may account for me rise in social problems such as environmental destruction
30 Which of the sentences below best expresses the essential information inthe highlighted sentencein the passage Incorrect choices change the meaning in important ways or leave out essential information
A tree will usually shed branches that use more carbohydrate than they produce
Branches that are shaded usually do not receive enough light to produce all the carbohydrate they need
If a tree gets rid of a branch it is usually because other branches lack enough carbohydrate to subsidize it
If a branch is shaded and cannot produce as muchcarbohydrate as it needs it will usually be subsidized by otherbranches
Preventing Overgrowth among Tree Branches
One way trees prevent themselves from having too many branches is simply by shedding (dropping off) branches once they have fulfilled their purpose This happens as the tree gets bigger and grows new outer layers of foliage that shade the inner and lower branches In most large trees the center of the canopy n contains only large branches small branches and fine twigs are found only at the canopy's edge In the shaded center the small branches that would once have occupied that space are long gone Trees like the true cypresses regularly shed small twigs complete with leaves toward the end of summer Most other trees shed only branches that prove unproductive If a branch is not producing enough carbohydrate to cover its own running costs—ie it needs to be subsidized by other branches because for example it is being shaded and receives little light—it will usually be got rid of This prevents unproductive branches from being a drain on the tree and removes the wind drag (the force of air resistance) from useless branches
31 According to paragraph 1 in what way do true cypresses differ from most other trees
Most small twigs on true cypresses have leaves attached to them
The shaded center areas of true cypresses are genera# occupied by many small twigs and branches
True cypresses shed twigs that grow on large unproductive branches
True cypresses seasonally shed small twigs without regard to whether they are productive or not
Paragraph 1 is marked with an arrow [ ]
Preventing Overgrowth among Tree Branches
One way trees prevent themselves from having too many branches is simply by shedding (dropping off) branches once they have fulfilled their purpose This happens as the tree gets bigger and grows new outer layers of foliage that shade the inner and lower branches In most large trees the center of the canopy n contains only large branches small branches and fine twigs are found only at the canopy's edge In the shaded center the small branches that would once have occupied that space are long gone Trees like the true cypresses regularly shed small twigs complete with leaves toward the end of summer Most other trees shed only branches that prove unproductive If a branch is not producing enough carbohydrate to cover its own running costs—ie it needs to be subsidized by other branches because for example it is being shaded and receives little light—it will usually be got rid of This prevents unproductive branches from being a drain on the tree and removes the wind drag (the force of air resistance) from useless branches
32 What best describes the relationship between paragraph 2 and the explanation offered in paragraph 1 for why most trees shed branches
Paragraph 2 questions this explanation
Paragraph 2 presents additional evidence supporting this explanation
Paragraph 2 discusses some additional reasons why trees shed branches
Paragraph 2 points out some additional consequences for trees besides the shedding of branches
Paragraph 1 and 2 are marked with an arrow [ ]
Preventing Overgrowth among Tree Branches
One way trees prevent themselves from having too many branches is simply by shedding (dropping off) branches once they have fulfilled their purpose This happens as the tree gets bigger and grows new outer layers of foliage that shade the inner and lower branches In most large trees the center of the canopy n contains only large branches small branches and fine twigs are found only at the canopy's edge In the shaded center the small branches that would once have occupied that space are long gone Trees like the true cypresses regularly shed small twigs complete with leaves toward the end of summer Most other trees shed only branches that prove unproductive If a branch is not producing enough carbohydrate to cover its own running costs—ie it needs to be subsidized by other branches because for example it is being shaded and receives little light—it will usually be got rid of This prevents unproductive branches from being a drain on the tree and removes the wind drag (the force of air resistance) from useless branches
Branches are shed for reasons other than lack of light In dry parts of the world it is common for trees and shrubs to lose smallerbranches to save water Small branches have the thinnest bark (the protective outer covering of a tree) and greatest surface area and thus are the source of most water loss once the leaves have been lost The creosote bush of United States deserts selfprunes or removes parts of itself in the face of extreme heal or drought starting from the highest and most exposed twigs and working downward to bigger and bigger branches it's a desperate act because if the creosote bush loses too much wood it dies Shedding branches can also be useful for selfpropagation Most poplar trees and willow trees characteristic of waterways will readily drop branches which take root when washed up on muddy banks further downstream
33 The word exposed’ in the passage is closest in meaning to
distant
unprotected
easily replaced
unproductive
Branches are shed for reasons other than lack of light In dry parts of the world it is common for trees and shrubs to lose smallerbranches to save water Small branches have the thinnest bark (the protective outer covering of a tree) and greatest surface area and thus are the source of most water loss once the leaves have been lost The creosote bush of United States deserts selfprunes or removes parts of itself in the face of extreme heal or drought starting from the highest and most exposed twigs and working downward to bigger and bigger branches it's a desperate act because if the creosote bush loses too much wood it dies Shedding branches can also be useful for selfpropagation Most poplar trees and willow trees characteristic of waterways will readily drop branches which take root when washed up on muddy banks further downstream
34 According to paragraph 2 what is true of the creosote bush of United States deserts
It tends to grow small branches during dry parts of the year
It loses more water through its bark than through ns leaves
It loses its louver branches only after losing upper ones
It sheds branches for the purpose of propagating itself
Paragraph 2 is marked with an arrow [ ]
Branches are shed for reasons other than lack of light In dry parts of the world it is common for trees and shrubs to lose smallerbranches to save water Small branches have the thinnest bark (the protective outer covering of a tree) and greatest surface area and thus are the source of most water loss once the leaves have been lost The creosote bush of United States deserts selfprunes or removes parts of itself in the face of extreme heal or drought starting from the highest and most exposed twigs and working downward to bigger and bigger branches it's a desperate act because if the creosote bush loses too much wood it dies Shedding branches can also be useful for selfpropagation Most poplar trees and willow trees characteristic of waterways will readily drop branches which take root when washed up on muddy banks further downstream
36 All of the following are mentioned in paragraph 3 as reasons that branches can be lost EXCEPT
being broken off by the wind
being shed for propagation
becoming rotten
becoming too large in diameter
Paragraph 3 is marked with an arrow [ ]
How are branches shed In the simplest cases dead branches rot and fall off or healthy branches are snapped off by wind snow and animals Some willows have a brittle zone at the base of small branches that encourage breaking in the wind seemingly for propagation Other cases of 'natural pruning' are more startling elm trees and to a certain extent others such as oaks have a reputation for dropping large branches (up to half a meter in diameter) with no warning on calm hot afternoons Such dramatic shedding appears to be due to a combination of internal water stress coupled with heat expansion affecting cracks and decayed wood
37 Which of the following is mentioned in paragraph 3 as playing a role in the shedding of large branches by elms and oaks on hot afternoons'
The development of a brittle zone at the base of the branchesThe enlargement of cracks in the branches due to heat
The rise of sudden bursts of wind that snap off decayed wood
The seasonal need to propagate new trees
Paragraph 3 is marked with an arrow [ ]
How are branches shed In the simplest cases dead branches rot and fall off or healthy branches are snapped off by wind snow and animals Some willows have a brittle zone at the base of small branches that encourage breaking in the wind seemingly for propagation Other cases of 'natural pruning' are more startling elm trees and to a certain extent others such as oaks have a reputation for dropping large branches (up to half a meter in diameter) with no warning on calm hot afternoons Such dramatic shedding appears to be due to a combination of internal water stress coupled with heat expansion affecting cracks and decayed wood
38 According to paragraph 4 what limits the possibility of harm resulting from the deliberate shedding of branches
Limiting the size of branches being shed to comparatively someones
Forming a new layer of wood to seal the wounded area immediately after shedding
Shedding leaves at the same time that branches are being shed
Forming a layer of protective tissue before branch shedding begins
Paragraph 4 is marked with an arrow [ ]
Many trees however shed branches deliberately in this situation branches are shed in the same way as foliage in autumn by the prior formation of a corky layer that leaves the wound sealed over with cork which in turn is undergrown with wood the followingyear In hardwoods branches up to a meter in length and several centimeters in diameter can be shed normally after the leaves have fallen in the autumn (maples are unusual in casting branches mainly in spring and early summer) Oaks tend to shed small twigs up to the thickness of a pencil beech may shed larger ones and birches dump whole branches of dead twigs Pine trees shed their clusters of needles (which really are short branches) and members of the redwood family shed their small branchlets with leaves Typically in hardwood trees something around 10 percent of terminal branches are lost each year through a mixture of deliberate shedding and being broken off
39 The word congestion’ in the passage is closest in meaning to
loss
damage
overcoming
stress
Another way of reducing potential congestion is to make some branches smaller than others Branches in shade grow smaller than those in the sun But trees can also regulate branch length from within In many trees there is a clear distinction between long and short branches or shoots The long shoots build the framework of the tree making it bigger The job of the short shoots (called spur shoots by horticultural) is to produce leaves and commonly flowers at more or less the same position every year To maintain flexibility any one shoot can switch from long to short or vice versa depending on internal factors light levels and damage
40 According to paragraph 5 what is the main purpose of short branches or shoots
To regulate the length of large branches
To increase the size of the trees
To produce leaves and flowers
To help create shaded areas
Paragraph 5 is marked with an arrow [ ]
Another way of reducing potential congestion is to make some branches smaller than others Branches in shade grow smaller than those in the sun But trees can also regulate branch length from within In many trees there is a clear distinction between long and short branches or shoots The long shoots build the framework of the tree making it bigger The job of the short shoots (called spur shoots by horticultural) is to produce leaves and commonly flowers at more or less the same position every year To maintain flexibility any one shoot can switch from long to short or vice versa depending on internal factors light levels and damage
41 Look at the four squares {} that indicate where the following sentence could be added to the passage
A tree will also shed branches if it water supply is insufficient
Where would the sentence best fit
Click on a square{} to add thesentence to the passage
Branches are shed for reasons other than lack of light In dry parts of the world it is common for trees and shrubs to lose smallerbranches to save waterSmall branches have the thinnest bark (the protective outer covering of a tree) and greatest surface area and thus are the source of most water loss once the leaves have been lost
The creosote bush of United States deserts selfprunes or removes parts of itself in the face of extreme heal or drought starting from the highest and most exposed twigs and working downward to bigger and bigger branches it's a desperate act because if the creosote bush loses too much wood it dies Shedding branches can also be useful for selfpropagation Most poplar trees and willow trees characteristic of waterways will readily drop branches which take root when washed up on muddy banks further downstream
TOEFL Writing
Some companies in the United States have developed wellness programs that give rewards or incentives to employees for achieving certain healthrelated goals such as stopping smoking or losing weight The rewards and incentives include cash prizes extra vacation days or reduction of the employee's portion of health insurance fees (in the United States health insurance fees are usually shared between the employer and the employee) Several arguments have been put forward in favor of the incentive programs
First the awards and incentives are an excellent motivational tool for people to adopt healthy lifestyles Many people would like to quit smoking or lose weight but have difficulty getting started The incentives provide the extra motivation they need One study suggests that giving people a cash incentive d^750 significantly increases their chances of quitting smoking And in another study people who got cash incentives were more likely to lose weight than those who did not
Second the advocates of incentive programs argue that rewarding people who are willing to adopt healthier lifestyles is only being fair People who exercise eat healthy diets and maintain a healthy weight for example are less likely to incur medical costs Such people deserve to pay smaller health insurance fees or get more vacation days
Third although the wellness incentives cost a lot of money for companies the incentives save companies money in the long term Losses in employee productivity due to illness can be very expensive for employers programs that help prevent health problems are cheap by comparison For example incentive programs have been shown to reduce the risk of diabetes and heart disease The cost ofthe incentives given by a company to its employees to maintain their health through prevention programs is much less than the financial losses to a company caused by employees missing work due to illness and hospitalization
TOEFL Writing
Do you agree or disagree with the following statement
When classmates or colleagues communicate about a project in person instead of by email they will produce better work for the project
Use specific reasons and examples to support your answer
Conversation 1
1 Why does the man go to see the registrar
○ To find out why he is not on the list of graduating students
○ To explain why he has not fulfilled his graduation requirements
○ To find out the exact requirements for graduation
○ To submit a document required for graduation
2 According to the registrar what step is currently taken to ensure that students fulfill their graduation requirements
○ Academic records are regularly checked by the registrar's office
○ Students meet with a department chairperson to plan their course work
○ Students receive letters listing the courses that they still need to take
○ Warning letters are sent to students who have fallen behind in their course work
3 Why does the man mention his classmates
○ To explain how he obtained information about field research
○ To point out that many students like to do field research
○ To show that it is difficult to get intermediatelevel credits
○ To emphasize his motivation to do filed research in two of his courses
4 Why does the registrar tell the man to contact his chairperson immediately
○ A deadline has already passed
○ The man has a limited time to resolve his problem
○ The man first needs to find out if the chairperson will help him
○ Issuing a new grade may take longer than expected
5 Listening again to part of the conversation Then answer the question
Why does the registrar imply when she says this
○ She is uncertain about the reliability of the computer
○ She will approve the man's form despite her doubts about it
○ She needs more information about the man's credits
○ She needs to call someone to help her fix computer errors
Lecture 1
6 What is the lecture mainly about
○ Recent fossil evidence connecting whales and the hippopotamus
○ Difficulties in the determining the evolutionary history of whales
○ Similarities among ancient ancestors of whales
○ Similarities between whales and other modernday animals
7 According to the professor what three aspects of the Ambulocetus fossil make Ambulocetus a likely bridge between land mammals and sea mammals
Click on 3 answers
○ It had an elongated skeletal structure
○ It strongly resembled a modern hippopotamus
○ It had an unusually kind and thin tail for a whale
○ It had limbs that could have been used for walking
○ Its skull had ear bones characteristic of land mammals
8 According to the professor what does the discovery of Ambulocetus mean to researchers
○ It fills a gap in the fossil evidence for whale evolution
○ It has become less significant since the discovery of Basilosaurus
○ It call into doubt the theory that whale evolved from land mammals
○ It suggests that whales evolved more recently than was previously believed
9 What evidence suggests that whale are descendants of the hippopotamus
○ Similarities between hippopotamus fossils and the Ambulocetus fossil
○ Similarities in the genes of hippopotamuses and whales
○ Similarities in the habitats of modern hippopotamuses and ancient whales
○ Similarities in the skeletal structures of modern hippopotamuses and ancient whales
10 What is the professor's opinion about recent genetic studies relating to whale evolution
○ They solve a longstanding mystery involving fossil evidence
○ They contain significant errors
○ They present evidence that conflicts with fossil evidence
○ The findings of the various studies should not have surprised researchers
11 What does DNA evidence indicate about relationships among whales
○ All modern whales descend from sperm whales
○ Differences among toothed whales are less significant that was previously thought
○ Not all toothed whales are closely related
○ Sperm whale are more closely related to killer whales than was previously thought
Lecture 2
12 What aspect of architecture in the United States is the lecture mainly about
○ The differences between rural and urban styles of housing
○ The reasons for popularity of a particular type of house
○ The various styles of houses that are popular in New England
○ The decorative details that are typical of houses built in New England
13 What is mentioned in the lecture as an application of the principle that form follows function
○ Smaller houses should have fewer rooms
○ A house's design should reflect the inhabitants' needs
○ The materials for a house should be selected before the house is designed
○ Houses in cold harsh climates should be built with inexpensive materials
14 Why does the woman refer to visiting her grandparents
○ To explain why she is interested in residential architecture
○ To explain why she knows a lot about the history of Cape Cod
○ To explain why she is familiar with Cape Cod houses
○ To explain why she enjoys visiting rural New England
15 According to the lecture what are two features of Cape Cod houses that were influenced by climate
Click on 2 answers
○ The thickness of walls
○ The slope of the roofs
○ The number of windows
○ The simplicity of the exterior
○ The size of the chimney
16According to the professor what contributed to the attitude of conformity in rural New England communities during the 1600s and 1700s
○ People depended on their neighbors for their own survival
○ People living in rural areas often had moved there from cities
○ People had to live very close to their neighbors
○ People had limited access to information from outside their community
17Why does the professor say this()
○ To indicate that the student's answer is wrong
○ To determine whether the student has prepared for the class
○ To point out that housing styles across the United States are very similar
○ To ask about students' preferences in architectural styles
Section 2
Conversation 2
1 What are the speakers mainly discussing
○ A book that the man is trying to find in the library
○ A book that the man already returned to the library
○ A book that the man is using to write his senior thesis
○ A book that the man lent to his sociology professor
2 What does the woman offer to do for the man
○ Let the man know when a book he needs is returned to the library
○ Photocopy a chapter of a book for him
○ Ask a professor to return a book the man needs
○ Find a copy of a book for him at another library
3 What is the woman trying to explain when she mentions students who have lost their borrowing privileges
○ Why the man should not photocopy part of the book
○ The reasons for one of the library's policies
○ What will happen if the man does not return the book
○ The reason the man has to fill out a form
4 How does the man probably feel at the end of the conversation
○ Annoyed that he has to pay a fine on the book
○ Upset that he will lose his library privileges
○ Glad that he can keep the book for two more weeks
○ Appreciative that the woman is helping him
5 Listen again to part of the conversation Then answer the question
Why does the woman say this …
○ To make sure she understands what the man's problem is
○ To encourage the man to return the book to the library soon
○ To check whether the man has already returned the book
○ To explain to the man a change in the library's policies
Lecture 3
6 What is the lecture mainly about
Click on 2 answers
○ Some changes that took place in the early years of opera
○ Difference between opera and other forms of music
○ Italy's musical influence throughout Europe
○ Reasons that early French and Italian opera did not survive
7 According to the professor what happened after the Italian language replaced Latin in Italian opera
○ Operas became much longer
○ Operas begin to express secular ideas
○ Music in opera became more complex
○ Opera was used to teach technology to the general public
8 Why does the professor mention ancient Greek theater
○ To give an example of a culture that adopted opera from the Italians
○ To describe the type of setting in which opera was typically performed
○ To point out a precursor of opera
○ To explain how opera was introduced into French society
9 What does the professor say about music in French opera
○ It resembled sacred church music
○ It often inspired French novelists to write great piece of literature
○ It revolved mainly around solo pieces
○ It was secondary to the rhythmic flow of language
10 What does the professor say this
○ To show difference between English and Italian opera
○ To give one instance in the evolution of opera
○ To discuss the popularity of opera in England at the time
○ To point out that English and Italian opera companies often worked together
11 What does the professor imply when he says this
○ He agrees with Chapman about opera and society
○ He thinks Chapman's approach to opera is confusing
○ He is concerned that Chapman's ideas are often misunderstood
○ He thinks Chapman's questions are difficult to answer
Lecture 4
12 What is the main topic of the lecture
○ The major differences between meteors and meteorites
○ The origins of comets and asteroids
○ The nature and origin of meteorites
○ The similarities between objects in the inner solar system
13 What comparison does the professor make to help describe the composition of
asteroids and comets
○ He compares them to stars
○ He compares them to types of planets
○ He compares them to rocks on Earth
○ He compares them to meteors and meteorites
14 What does the professor say about the origin of meteors and meteorites
○ They are pieces of asteroids or comets
○ They are pieces of the planets in our solar system
○ They are made from minerals that are otherwise uncommon in our solar system
○ Their origin cannot be determined
15 According to the professor what feature of a meteoroid generally determines whether the meteoroid becomes a meteorite
○ Whether it was originally part of a larger meteoroid
○ Whether it originated in the inner or outer solar system
○ What proportion of iron and stone it contains
○ How large it is when it enters Earth's atmosphere
16 What are two points the professor makes about stone meteorites
Click on 2 answers
○ They are the type of meteorite that most commonly falls to the ground
○ They are the type of meteorite most often seen in museums
○ They are the oldest type of meteorite found on the ground
○ They are the most difficult type of meteorite to find on the ground
17 Why does the professor say this
○ To offer a hint about the answer to a question he asked
○ To clarify a question that a student asked
○ To find out whether students understand a question he asked
○ To find out whether students understand an important comparison he made
Speaking
Task 1 Which of the following activities would you be more interested in doing Teaching children teaching adults to use computers or cleaning city park
Task 2 Some people prefer take a job with a single task others prefer to do multiple tasks on a job Which do you prefer
Task 3
The school plans to start a student art club so that students can learn about art and still pursue their major and the club will offer affordable museum tickets for students to see art
The man in the conversation agrees
First he really loved art in high school but now he majors in chemistry and doesn’t have time for art The new art club would be a good chance for him to pursue art and he doesn’t have to worry about how it would affect his major because he doesn’t need to go to an actual class and get credits
Second the museum is too expensive for many students to go to so this would be a good chance for them to enjoy art they could not see before
Task 4
The professor talks about logical consequences which means teachers use logical consequences to link students’ wrong behavior with its negative consequences to correct it
In the example when the professor was teaching little kids sometimes he would let them use pens to paint A girl called Mary would paint on the desk and damage the facilities He first punished her by not allowing her to play outside with other kids but it didn’t work Mary painted on the desk again This time the professor warned her that if she didn’t stop the behavior he would not let her paint next time So Mary corrected her wrong behavior afterwards
Task 5
The man’s problem is that he’s moving into a new apartment and needs to move his old stuff to the new apartment and he’s thinking about how The first solution is that he can rent a truck but the small trucks are all rented out and big trucks are expensive
The second solution is he can borrow his friend’s car but it’s kind of small and he will have to go back and forth a few times
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