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THE SCIENCE OF ANTHROPOLOGY

(1) Through various methods of research, anthropologists try to fit together the pieces of the human puzzle—to discover how humanity was first achieved, what made it branch out in different directions, and why separate societies behave similarly in some ways but quite differently in other ways. (2) Anthropology, which emerged as an independent science in the late eighteenth century, has two main divisions: physical anthropology and cultural anthropology. (3) Physical anthropology focuses on human evolution and variation and uses methods of physiology, genetics, and ecology. Cultural anthropology focuses on culture and includes archaeology, social anthropology, and linguistics. (4)

Physical anthropologists are most concerned with human biology. Physical anthropologists are detectives whose mission is to solve the mystery of how humans came to be human. They ask questions about the events that led a tree-dwelling population of animals to evolve into two-legged beings with the power to learn—a power that we call intelligence. Physical anthropologists study the fossils and organic remains of once-living primates. They also study the connections between humans and other primates that are still living. Monkeys, apes, and humans have more in common with one another physically than they do with other kinds of animals. In the lab, anthropologists use the methods of physiology and genetics to investigate the composition of blood chemistry for clues to the relationship of humans to various primates. Some study the animals in the wild to find out what behaviors they share with humans. Others speculate about how the behavior of non-human primates might have shaped human bodily needs and habits.

A well-known family of physical anthropologists, the Leakeys, conducted research in East Africa indicating that human evolution centered there rather than Asia. In 1931, Louis Leakey and his wife Mary Leakey began excavating at Olduvai Gorge in Tanzania, where over the next forty years they discovered stone tool and hominid evidence that pushed back the dates for early humans to over 3.75 million years ago. Their son, Richard Leakey, discovered yet other types of hominid skulls in Kenya, which he wrote about in Origins (1979) and Origins Reconsidered (1992).

Like physical anthropologists, cultural anthropologists study clues about human life in the distant past; however, cultural anthropologists also look at the similarities and differences among human communities today. Some cultural anthropologists work in the field, living and working among people in societies that differ from their own. Anthropologists doing fieldwork often produce an ethnography, a written description of the daily activities of men, women, and children that tells the story of the society’s community life as a whole. Some cultural anthropologists do not work in the field but rather at research universities and museums doing the comparative and interpretive part of the job. These anthropologists, called ethnologists, sift through the ethnographies written by field anthropologists and try to discover cross-cultural patterns in marriage, child rearing, religious beliefs and practices, warfare—any subject that constitutes the human experience. They often use their findings to argue for or against particular hypotheses about people worldwide.

A cultural anthropologist who achieved worldwide fame was Margaret Mead. In 1923, Mead went to Samoa to pursue her first fieldwork assignment—-a study that resulted in her widely read book Coming of Age in Samoa (1928). Mead published ten major works during her long career, moving from studies of child rearing in the Pacific to the cultural and biological bases of gender, the nature of cultural change, the structure and functioning of complex societies, and race relations. Mead remained a pioneer in her willingness to tackle subjects of major intellectual consequence, to develop new technologies for research, and to think of new ways that anthropology could serve society.

Glossary:

- primates: the order of mammals that includes apes

- humans hominid: the family of primates of which humans are the only living species

1. The phrase “branch out” in paragraph 1 is closest in meaning to ................

A.

look

B.

originate

C.

hurry

D.

separate

Explain:

2. Which sentence below best expresses the essential information in the highlighted sentence in paragraph 2? Incorrect choices change the meaning in important ways or leave out essential information.

A.

Some animal populations have the power to ask questions and to learn from the events of the past.

B.

People want to know more about the behavior of animals and how some animals acquire the ability to learn.

C.

There are unanswered questions about why some tree-dwelling animals have evolved only two legs.

D.

Physical anthropologists investigate how intelligent human beings evolved from creatures that lived in trees.

Explain:

3. The word “speculate” in paragraph 2 is closest in meaning to ................

A.

forget

B.

think

C.

disagree

D.

worry

Explain:

4. Why does the author discuss the Leakey family in paragraph 3?

A.

To argue for an increase in the amount of research in Africa

B.

To contradict earlier theories of human evolution

C.

To give examples of fieldwork done by physical anthropologists

D.

To compare hominid evidence from Tanzania with that from Kenya

Explain:

5. Which of the following is of major interest to both physical and cultural anthropologists?

A.

Clues about human beings who lived long ago

B.

Methods of physiology and genetics

C.

Religious beliefs and practices

D.

Child rearing in societies around the world

Explain:

6. According to paragraph 4, cultural anthropologists who do fieldwork usually ................

A.

write an account of the daily life of the people they study

B.

discover hominid evidence indicating when humans evolved

C.

work at universities and museums interpreting the work of others

D.

develop new technologies for gathering cultural data

Explain:

7. The phrase “sift through” in paragraph 4 is closest in meaning to ................

A.

contradict

B.

sort

C.

avoid

D.

discuss

Explain:

8. The word “They” in paragraph 4 refers to ................

A.

museums

B.

field anthropologists

C.

research universities

D.

ethnologists

Explain:

9. According to the passage, Margaret Mead wrote about all of the following subjects EXCEPT ................

A.

the biological basis of gender

B.

economic systems of pioneer women

C.

relations between people of different races

D.

the nature of cultural change

Explain:

10. It can be inferred from paragraph 5 that Margaret Mead′s work ................

A.

opened Samoa to outside influences

B.

contradicted that of the Leakey family

C.

is not widely read by anthropologists today

D.

made an impact on the field of anthropology

Explain:

11. Look at the four numbers (1), (2), (3) and (4) which indicate where the sentence “Anthropology is the study of the origin, development, and varieties of human beings and their societies.” could be added to the passage. Where would the sentence best fit?

A.

Number 3

B.

Number 2

C.

Number 4

D.

Number 1

Explain:

12. Choose THREE sentences that describe the Physical Anthropology

A.

Researchers live and work in other societies and write ethnographies.

B.

This field studies life on many different scales of size and time.

C.

Scientists examine the fossils and skulls of early humans.

D.

Researchers observe similarities between humans and other primates.

E.

The focus is on the similarities and differences among cultures.

F.

It is the study of the origin, history, and structure of the earth.

G.

The story of humanity's origins is a major topic of investigation.

Explain:

13. Choose TWO sentences that describe the Cultural Anthropology

A.

The story of humanity's origins is a major topic of investigation.

B.

This field studies life on many different scales of size and time.

C.

Researchers observe similarities between humans and other primates.

D.

Researchers live and work in other societies and write ethnographies.

E.

Scientists examine the fossils and skulls of early humans.

F.

It is the study of the origin, history, and structure of the earth.

G.

The focus is on the similarities and differences among cultures.

Explain:

FACTORS THAT INFLUENCE TIDES

Tides are a natural phenomenon involving the alternating rise and fall in the earth’s large bodies of water caused by the gravitational pull of the moon and the sun. The combination of these two variable forces produces the complex recurrent cycle of the tides. Tides may occur in both oceans and seas, to a limited extent in large lakes, the atmosphere, and, to a very minute degree, in the earth itself.

The force that generates tides results from the interaction of two forces: the centrifugal force produced by the revolution of the earth around the center-of-gravity of the earth - moon system; and the gravitational attraction of the moon acting upon the earth’s waters. Although the moon is only 238,852 miles from the earth, compared with the sun’s much greater distance of 92,956,000 miles, the moon’s closer distance outranks its much smaller mass, and thus the moon’s tide-raising force is more than twice that of the sun.

The tide-generating forces of the moon and sun ‘cause a maximum accumulation of the waters of the oceans at two opposite positions on the earth’s surface. At the same time, compensating amounts of water are drawn from all points 90 degrees away from these tidal bulges. As the earth rotates, a sequence of two high tides and two low tides is produced each day. Successive high tides occur on an average of 12.4 hours apart. High tide at any given location occurs when the moon is overhead and low tide when it is at either horizon.

The highest and lowest levels of high tide, called spring tide and neap tide, each occur twice in every lunar month of about 27.5 days. A spring tide occurs at the new moon and at the full moon, when the moon and earth are lined up with the sun, and thus the moon’s pull is reinforced by the sun’s pull. At spring tide, the difference between high and low tides is the greatest. A neap tide, the lowest level of high tide, occurs when the sun-to- earth direction is at right angles to the moon-to-earth direction. When this happens, the gravitational forces of the moon and sun counteract each other: thus, the moon’s pull is at minimum strength, and the difference between high and low tides is the least. Spring and neap tides at any given location have a range of about 20 percent more or less, respectively, than the average high tide.

The vertical range of tides—the difference between high and low—varies according to the size, surface shape, and bottom topography of the basin in which tidal movement occurs. In the open water of the central Pacific, the range is no more than about a foot; in the relatively small, shallow North Sea, it is about 12 feet. Along the narrow channel of the Bay of Fundy in Nova Scotia, the difference between high and low tides may reach 45 feet under spring tide conditions—the world’s widest tidal range. At New Orleans, which is at the mouth of the Mississippi River, the periodic rise and fall of the tides varies with the river’s stage, being about ten inches at low stage and zero at high. In every case, actual high or low tide can vary considerably from the average.

Several factors affect tidal ranges, including abrupt changes in atmospheric pressure or prolonged periods of extreme high or low pressure. (1) They are also influenced by the density and volume of seawater, variations in ocean-current velocities, earthquakes, and the growing or shrinking of the world’s glaciers. (2) In fact, any of these factors alone can alter sea level. (3) The greater and more rapid the change of water level, the greater the erosive effect of the tidal action, and thus in the amount of material transported and deposited on the shore. (4)

14. The word “recurrent” in paragraph 1 is closest in meaning to

A.

simultaneous

B.

interrupted

C.

repeating

D.

mysterious

Explain:

15. According to the passage, the force that generates tides on the earth is

A.

abrupt changes in atmospheric pressure

B.

a combination of gravity and centrifugal force

C.

the same force that generates tides on the moon

D.

the gravitational pull of the earth's core

Explain:

16. According to the passage, the moon

A.

is farther from the earth than the sun

B.

has a gravitational pull toward the sun

C.

has a greater mass than the sun

D.

affects tides more than the sun does

Explain:

17. The word “bulges” in paragraph 3 is closest in meaning to

A.

currents

B.

waves

C.

increases

D.

ridges

Explain:

18. What can be inferred from paragraph 3 about tides in different places on the earth?

A.

The time between high and low tides is the same in different places.

B.

When it is high tide in some places, it is low tide in other places.

C.

High tide occurs at every location on the earth at the same time.

D.

Some places have two high tides each day, but others have only one.

Explain:

19. A spring tide occurs at the time of the lunar month when

A.

the moon appears as a crescent or half-circle

B.

the sun does not exert any gravitational force

C.

the moon's gravitational pull is at its strongest

D.

the difference between high and low tides is the least

Explain:

20. The word “counteract” in paragraph 4 is closest in meaning to

A.

signal

B.

avoid

C.

oppose

D.

enhance

Explain:

21. Which sentence below best expresses the essential information in the highlighted sentence in paragraph 4? Incorrect choices change the meaning in important ways or leave out essential information.

A.

20 percent of both spring tides and neap tides always occur in the same location.

B.

If the location of a spring tide is known, then a neap tide in the same location will be 20 percent less.

C.

Spring tides are 20 percent more, and neap tides 20 percent less, than the average high tide in a particular place.

D.

There has been a 20 percent change in the number of spring tides and neap tides that occur at certain locations.

Explain:

22. The author mentions “the Bay of Fundy” in paragraph 5 in order to

A.

explain why a narrow channel is dangerous to ships

B.

compare the Bay of Fundy with larger bodies of water

C.

show how rivers can affect the rise and fall of tides

D.

give the most extreme example of a tidal range

Explain:

23. The word prolonged in paragraph 6 is closest in meaning to

A.

predicted

B.

extended

C.

surprising

D.

dangerous.

Explain:

24. All of the following are mentioned as influences on the vertical range of tides EXCEPT

A.

changes in the size of the world's glaciers

B.

increasing levels of pollution in the oceans

C.

sudden changes in atmospheric pressure

D.

the size and shape of the body of water

Explain:

25. Look at the four numbers (1), (2), (3) and (4) which indicate where the sentence “Storm surges, such as the heaping up of ocean water by hurricane winds, are yet another factor.” could be added to the passage. Where would the sentence best fit?

A.

Number 3

B.

Number 2

C.

Number 4

D.

Number 1

Explain:

26. An introductory sentence for a brief summary of the passage is: “Many factors influence the phenomenon of tides, the alternating rise and fall in the earth′s large bodies of water.” Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage.

A.

The gravitational forces of the moon and the sun together produce the cycle of the tides.

B.

Scientists have been studying the moon's influence on tides for several centuries.

C.

The level of high tide varies throughout the lunar month.

D.

The stage of the Mississippi River determines the level of tides at New Orleans.

E.

Tides occur in the earth's atmosphere and also in the earth itself.

F.

The character of the basin and various environmental conditions affect the vertical range of tides.

Explain:

MUSICAL TALENT

Among all the abilities with which an individual may be endowed, musical talent appears earliest in life. Very young children can exhibit musical precocity for different reasons. Some develop exceptional skill as a result of a well-designed instructional regime, such as the Suzuki method for the violin. Some have the good fortune to be born into a musical family in a household filled with music. In a number of interesting cases, musical talent is part of an otherwise disabling condition such as autism or mental retardation. A musically gifted child has an inborn talent; however, the extent to which the talent is expressed publicly will depend upon the environment in which the child lives.

Musically gifted children master at an early age the principal elements of music, including pitch and rhythm. Pitch—or melody—is more central in certain cultures, for example, in Eastern societies that make use of tiny quarter-tone intervals. Rhythm, sounds produced at certain auditory frequencies and grouped according to a prescribed system, is emphasized in sub-Saharan Africa, where the rhythmic ratios can be very complex.

All children have some aptitude for making music. (1) During infancy, normal children sing as well as babble, and they can produce individual sounds and sound patterns. (2) Infants as young as two months can match their mother’s songs in pitch, loudness, and melodic shape, and infants at four months can match rhythmic structure as well. (3) Infants are especially predisposed to acquire these core aspects of music, and they can also engage in sound play that clearly exhibits creativity. (4)

Individual differences begin to emerge in young children as they learn to sing. Some children can match large segments of a song by the age of two or three. Many others can only approximate pitch at this age and may still have difficulty in producing accurate melodies by the age of five or six. However, by the time they reach school age, most children in any culture have a schema of what a song should be like and can produce a reasonably accurate imitation of the songs commonly heard in their environment.

The early appearance of superior musical ability in some children provides evidence that musical talent may be a separate and unique form of intelligence. There are numerous tales of young artists who have a remarkable “ear” or extraordinary memory for music and a natural understanding of musical structure. In many of these cases, the child is average in every other way but displays an exceptional ability in music. Even the most gifted child, however, takes about ten years to achieve the levels of performance or composition that would constitute mastery of the musical sphere.

Every generation in music history has had its famous prodigies—individuals with exceptional musical powers that emerge at a young age. In the eighteenth century, Wolfgang Amadeus Mozart began composing and performing at the age of six. As a child, Mozart could play the piano like an adult. He had perfect pitch, and at age nine he was also a master of the art of modulation—transitions from one key to another—which became one of the hallmarks of his style. By the age of eleven, he had composed three symphonies and 30 other major works. Mozart’s well-developed talent was preserved into adulthood.

Unusual musical ability is a regular characteristic of certain anomalies such as autism. In one case, an autistic girl was able to play “Happy Birthday” in the style of various composers, including Mozart, Beethoven, Verdi, and Schubert. When the girl was three, her mother called her by playing incomplete melodies, which the child would complete with the appropriate tone in the proper octave. For the autistic child, music may be the primary mode of communication, and the child may cling to music because it represents a haven in a world that is largely confusing and frightening.

Glossary:

- schema: a mental outline or model

- anomaly: departure from what is normal; abnormal condition

- autism: a developmental disorder involving impaired communication and emotional separation

27. The word “precocity” in paragraph 1 is closest in meaning to ................

A.

personal style

B.

advanced skill

C.

strong interest

D.

good luck

Explain:

28. Which sentence below best expresses the essential information in the highlighted sentence in paragraph 1? Incorrect choices change the meaning in important ways or leave out essential information.

A.

Children with exceptional musical talent will look for the best way to express themselves through music-making.

B.

Children may be born with superior musical ability, but their environment will determine how this ability is developed.

C.

Every child is naturally gifted, and it is the responsibility of the public schools to recognize and develop these talents.

D.

Some musically talented children live in an environment surrounded by music, while others have little exposure to music.

Explain:

29. The author makes the point that musical elements such as pitch and rhythm ................

A.

express different human emotions

B.

vary in emphasis in different cultures

C.

make music difficult to learn

D.

distinguish music from other art forms

Explain:

30. The word “predisposed” in paragraph 3 is closest in meaning to ................

A.

amused

B.

gifted

C.

pushed

D.

inclined

Explain:

31. According to the passage, when does musical talent usually begin to appear?

A.

between ten years old and adolescence

B.

between the ages of two and four months

C.

When children learn to sing at two or three years old

D.

When infants start to babble and produce sound patterns

Explain:

32. According to the passage, which of the following suggests that musical talent is a separate form of intelligence?

A.

Recognition of the emotional power of music

B.

Exceptional musical ability in an otherwise average child

C.

Differences between learning music and learning language

D.

the ability of all babies to acquire core elements of music

Explain:

33. Why does the author discuss Mozart in paragraph 6?

A.

to describe the development of individual musical skill

B.

to compare past and present views of musical talent

C.

To give an example of a well-known musical prodigy

D.

to list musical accomplishments of the eighteenth century

Explain:

34. In music, the change from one key to another is known as ................

A.

prodigy

B.

modulation

C.

rhythm

D.

perfect pitch

Explain:

35. All of the following are given as examples of exceptional musical talent EXCEPT ................

A.

appreciation for a wide variety of musical styles

B.

a remarkable “ear” or perfect memory for music

C.

ability to compose major works at a young age

D.

playing a single song in the style of various composers

Explain:

36. The word “haven” in paragraph 7 is closest in meaning to ................

A.

simple problem

B.

beautiful art

C.

personal goal

D.

safe place

Explain:

37. Which of the following can be inferred from the passage about exceptional musical ability?

A.

It is the result of natural talent and a supportive environment.

B.

It has been documented and studied but is little understood.

C.

It is evidence of a superior level of intelligence in other areas.

D.

occurs more frequently in some cultures than in others.

Explain:

38. Look at the four numbers (1), (2), (3) and (4) which indicate where the sentence “They can even imitate patterns and tones sung by other people.” could be added to the passage. Where would the sentence best fit?

A.

Number 1

B.

Number 3

C.

Number 2

D.

Number 4

Explain:

39. An introductory sentence for a brief summary of the passage is: “Musical talent usually appears early in life.” Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage.

A.

Very young children can develop exceptional skill in playing the violin by the Suzuki method.

B.

Prodigies have a natural understanding of musical structure that enables them to play and compose music with great skill.

C.

Wolfgang Amadeus Mozart had composed several major works and symphonies by the age of eleven

D.

While all children have a basic ability to make music, some exhibit extraordinary skill at a very early age.

E.

Exceptional musical ability is often part of an otherwise disabling condition such as autism.

F.

Autistic children cannot relate to their environment realistically and therefore have difficulty in communicating.

Explain:

THE GREENHOUSE EFFECT AND GLOBAL WARMING

Carbon dioxide and other naturally occurring gases in the earth’s atmosphere create a natural greenhouse effect by trapping and absorbing solar radiation. These gases act as a blanket and keep the planet warm enough for life to survive and flourish. The warming of the earth is balanced by some of the heat escaping from the atmosphere back into space. Without this compensating flow of heat out of the system, the temperature of the earth’s surface and its atmosphere would rise steadily.

Scientists are increasingly concerned about a human-driven greenhouse effect resulting from a rise in atmospheric levels of carbon dioxide and other heat-trapping greenhouse gases. The man-made greenhouse effect is the exhalation of industrial civilization. A major contributing factor is the burning of large amounts of fossil fuels—coal, petroleum, and natural gas. Another is the destruction of the world’s forests, which reduces the amount of carbon dioxide converted to oxygen by plants. Emissions of carbon dioxide, chlorofluorocarbons. nitrous oxide, and methane from human activities will enhance the greenhouse effect, causing the earth’s surface to become warmer. The main greenhouse gas, water vapor, will increase in response to global warming and further enhance it.

There is agreement within the scientific community that the buildup of greenhouse gases is already causing the earth’s average surface temperature to rise. This is changing global climate at an unusually fast rate. According to the World Meteorological Organization, the earth’s average temperature climbed about 1 degree F in the past century, and nine of the ten warmest years on record have occurred since 1990. A United Nations panel has predicted that average global temperatures could rise as much as 10.5 degrees F during the next century as heat-trapping gases from human industry accumulate in the atmosphere.

What are the potential impacts of an enhanced greenhouse effect? According to estimates by an international committee, North American climatic zones could shift northward by as much as 550 kilometers (340 miles). Such a change in climate would likely affect all sectors of society. In some areas, heat and moisture stress would cut crop yields, and traditional farming practices would have to change. For example, in the North American grain belt, higher temperatures and more frequent drought during the growing season might require farmers to switch from corn to wheat and to use more water for irrigation.

Global warming may also cause a rise in sea level by melting polar ice caps. A rise in sea level would accelerate coastal erosion and inundate islands and low-lying coastal plains, some of which are densely populated. Millions of acres of coastal farmlands would be covered by water. Furthermore, the warming of seawater will cause the water to expand, thus adding to the potential danger.

Global warming has already left its fingerprint on the natural world. Two research teams recently reviewed hundreds of published papers that tracked changes in the range and behavior of plant and animal species, and they found ample evidence of plants blooming and birds nesting earlier in the spring. Both teams concluded that rising global temperatures are shifting the ranges of hundreds of species—thus climatic zones—northward. These studies are hard evidence that the natural world is already responding dramatically to climate change, even though the change has just begun. If global warming trends continue, changes in the environment will have an enormous impact on world biology. Birds especially play a critical role in the environment by pollinating plants, dispersing seeds, and controlling insect populations; thus, changes in their populations will reverberate throughout the ecosystems they inhabit.

40. According to the passage, how do carbon dioxide and other greenhouse gases affect the earth-atmosphere system?

A.

They cause heat to flow from the atmosphere into space.

B.

They collect solar radiation that warms the earth's surface.

C.

They create the conditions for new forms of life to emerge.

D.

They decrease the amount of oxygen in the atmosphere.

Explain:

41. All of the following are contributing factors to global warming EXCEPT ................

A.

the conversion of carbon dioxide to oxygen

B.

the buildup of water vapor in the atmosphere

C.

the loss of forest lands

D.

the burning of coal and petroleum

Explain:

42. The word “enhance” in paragraph 2 is closest in meaning to ................

A.

stabilize

B.

counteract

C.

strengthen

D.

parallel

Explain:

43. What can be inferred from paragraph 3 about global climate change?

A.

Climate change is likely to continue as long as heat-trapping gases accumulate.

B.

International organizations have been studying climate change only since 1990.

C.

It is difficult to predict the effects of climate change over the next century.

D.

Climate change will have both positive and negative effects on human society.

Explain:

44. According to paragraph 4, what is one effect that climate change could have on agriculture in North America?

A.

Changes in the crops that farmers can grow

B.

Movement of farms to the northernmost regions

C.

Less water available for irrigating crops

D.

Return to more traditional methods of farming

Explain:

45. The word “inundate” in paragraph 5 is closest in meaning to ................

A.

create

B.

reduce

C.

move

D.

cover

Explain:

46. Why does the author use the word “fingerprint” in paragraph 6?

A.

To show that hundreds of fingerprints were examined

B.

To suggest that people do not cause global warming

C.

To describe a method used by two research teams

D.

To introduce conclusive evidence of global warming

Explain:

47. The word “they” in paragraph 6 refers to ................

A.

papers

B.

birds

C.

species

D.

teams

Explain:

48. The word “hard” in paragraph 6 is closest in meaning to ................

A.

secret

B.

real

C.

difficult

D.

contradictory

Explain:

49. What evidence does the author give that climatic zones have shifted northward?

A.

Solar radiation escapes from the atmosphere back into space.

B.

Plants bloom and birds build nests earlier in the spring.

C.

The water in the ocean expands as it gets warmer.

D.

Birds no longer pollinate plants or control insect populations.

Explain:

50. Look at the four numbers (1), (2), (3) and (4) which indicate where the sentence “The combination of melting ice caps with the expansion of water could raise the sea level several centimeters by the year 2100.” could be added to the passage. Where would the sentence best fit?

A.

Number 3

B.

Number 2

C.

Number 4

D.

Number 1

Explain:

51. An introductory sentence for a brief summary of the passage is: “Scientists are concerned about the greenhouse effect and its role in global warming.” Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage.

A.

Nine of the ten warmest years on record have occurred since 1990.

B.

Global warming will alter the range and behavior of plants and animals, changing the balance of ecosystems.

C.

A rise in atmospheric levels of carbon dioxide and other greenhouse gases is causing the earth's surface to become warmer.

D.

Global warming could result in job loss for millions of farmers in coastal areas.

E.

Some scientists think the temperature trend indicates man-made global warming, while others believe it is natural climate variability.

F.

A rising sea level and shifts in climatic zones are probable effects of global warming.

Explain:

ESTUARIES

Fresh water from land enters the ocean through rivers, streams, and groundwater-flowing through valleys. These valleys that channel fresh water from land to the salty ocean, which range from extremely narrow stream-cut channels to remarkably broad lagoons behind long barrier islands, are called estuaries.

A number of types of estuaries are commercially vital. Many commercially important estuaries are the mouths of major rivers. The powerful flow of water in major rivers maintains channels that are deep enough for navigation by ocean-bound vessels, and the rivers themselves provide transportation of goods to points farther inland. In addition, estuaries formed as a result of tectonic or glacial activity are sometimes sufficiently deep to provide ports for oceangoing vessels. The types of estuaries that are not viable as ports-of-call for ocean commerce are those that are not wide enough, not deep enough, and not powerful enough to prevent the buildup of sediment.

Estuary systems, which vary to reject the geology of the coasts where they are found, can be broadly categorized as one of two different types. One type of estuary system is the type that is found in flooded coastal plains, the broad land areas that extend out to the continental shelves, on the Atlantic coasts of North and South America, Europe, and Africa, for example. The other category of estuary system encompasses the mountainous coasts, with their rugged topography, such as those found along the Pacific coasts of North and South America.

Today, much of the eastern coast of the United States is a flooded coastal plain. During the last ice age, much of what is today the submerged continental shelf was exposed as an extended part of the continent. Intricate river systems composed of main rivers and their tributaries cut valleys across the plains to the edge of the shelf, where they released the fresh water that they carried into the ocean. Then, as the ice melted at the end of the ice age, rising waters extended inland over the lower areas, creating today’s broad drowned river valleys. On today’s flooded coastal plains, the water is comparatively shallow and huge amounts of sand and sediment are deposited. (1)These conditions foster the growth of extensive long and narrow offshore deposits, many of which are exposed above the water as sandspits or barrier islands. (2)These Deposits are constantly being reshaped, sometimes extremely slowly and sometimes quite rapidly, by the forces of water and wind. (3)It is common along flooded coastal plains for drowned river valleys to empty into lagoons that have been created behind the sandspits and barrier islands rather than emptying directly into the ocean. (4)These lagoons support vigorous biological activity inasmuch as they are shallow, which causes them to heat up quickly, and they are fed by a constant inflow of nutrient-rich sediments.

Unlike the flooded coastal plains, the mountainous coasts have a more rugged and irregular topography with deeper coastal waters. There is less sand and sediment, and external systems of barrier islands are not as pervasive as they are on flooded coastal plains because the mountainous topography blocks the flow of sediments to the coast and because the deeper ocean water inhibits the growth of barrier islands, and without the protection of barrier beaches, mountainous coasts are more exposed to direct attack by the erosive forces of waves. Different geological processes contribute to the rugged topography along mountain coasts. The tectonic activity that creates the mountains along a mountainous coast can cause large blocks of the Earth's crust tc fall below sea level; San Francisco Bay in California and the Strait of Juan de Fuca in Washington state in the north formed in this way. In the northern latitudes, coastal fjords were created as glaciers cut impressive u-shaped valleys through mountains and now carry fresh water from the land to the ocean.

52. The phrase “commercially vital” in paragraph 2 is closest in meaning to ................

A.

understandably lucky

B.

by-products of business

C.

the essence of professionality

D.

important to trade

Explain:

53. The word “viable” in paragraph 2 is closest in meaning to ................

A.

valuable

B.

identifiable

C.

verifiable

D.

workable

Explain:

54. The passage indicates that all of the following are estuaries with commercial potential as ports of call EXCEPT ................

A.

estuaries at the mouths of powerful rivers

B.

estuaries formed from tectonic activity

C.

estuaries formed by glaciers

D.

estuaries on flooded coastal plains

Explain:

55. The word “Intricate” in paragraph 4 is closest in meaning to ................

A.

individual

B.

attractive

C.

delicate

D.

complex

Explain:

56. According to the passage, drowned river valleys ................

A.

are covered with deep water

B.

are covered with shallow water

C.

are covered with ice

D.

are land areas with rivers cutting through

Explain:

57. The word “foster” in paragraph 4 is closest in meaning to ................

A.

deter

B.

relate

C.

encourage

D.

adopt

Explain:

58. Look at the four numbers (1), (2), (3) and (4) which indicate where the sentence “Some changes to the deposits can take place gradually over decades, while other changes can be quite radical changes in a period of only a few hours as the result of major storm activity.” can be added to paragraph 4. Where would the sentence best fit?

A.

Number 2

B.

Number 3

C.

Number 1

D.

Number 4

Explain:

59. Which of the sentences below expresses the essential information in the highlighted sentence in paragraph 4? Incorrect choices change the meaning in important ways or leave out essential information.

A.

Biological activity contributes to the formation of lagoons by heating them up and providing a source of food.

B.

The flow of sediments into lagoons causes biological activity, which in turn causes the lagoons to heat up.

C.

A lot of life exists in lagoons for two reasons: the low water level and the steady source of new residue.

D.

Lagoons become more and more shallow as they heat up and flow into the ocean.

Explain:

60. The author begins paragraph 5 with the phrase “Unlike the flooded coastal plains” in order to ................

A.

indicate that a thorough discussion of flooded coastal plains follows

B.

show that flooded coastal plains and mountainous coasts have some similarities in spite of their differences

C.

clarify the ideas of flooded coastal plains that were previously presented

D.

indicate that the discussion is moving from one type of estuary system to the other

Explain:

61. The phrase “not as pervasive as” in paragraph 5 is closest in meaning to ................

A.

not as limited as

B.

less common than

C.

as simple as

D.

more covered than

Explain:

62. The phrase “this way” in paragraph 5 refers to ................

A.

large blocks of crust sinking as a result of tectonic activity

B.

the sea level rising along the mountainous coast

C.

glaciers cutting valleys through mountains

D.

geological processes contributing to rugged topography

Explain:

63. It is implied in the passage that fjords ................

A.

are a type of mountainous estuary system

B.

are found throughout the world

C.

have as much sediment as flooded coastal plains

D.

were formed in the same way as the San Francisco Bay

Explain:

64. Choose FOUR phrases that describe the estuary systems on flooded coastal plains

A.

Are protected by barrier beaches

B.

Are never commercially viable

C.

Are the primary way that fresh water is channeled to the ocean

D.

Are not protected by barrier beaches

E.

Were created by tectonic or glacial activity

F.

Have huge amounts of deposits

G.

Were created on part of a submerged continent

H.

Have smaller amounts of deposits

I.

Lead into deeper bodies of water

G.

Are covered with shallow water

Explain:

65. Choose FOUR phrases that describe the estuary systems on mountainous coasts

A.

Have huge amounts of deposits

B.

Are protected by barrier beaches

C.

Were created by tectonic or glacial activity

D.

Are the primary way that fresh water is channeled to the ocean

E.

Have smaller amounts of deposits

F.

Lead into deeper bodies of water

G.

Are covered with shallow water

H.

Were created on part of a submerged continent

I.

Are never commercially viable

G.

Are not protected by barrier beaches

Explain:

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