ISEE Upper Level Reading : Language in Science Passages

Study concepts, example questions & explanations for ISEE Upper Level Reading

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Example Questions

Example Question #51 : Science Passages

Adapted from "How the Soil is Made" by Charles Darwin in Wonders of Earth, Sea, and Sky (1902, ed. Edward Singleton Holden)

Worms have played a more important part in the history of the world than most persons would at first suppose. In almost all humid countries they are extraordinarily numerous, and for their size possess great muscular power. In many parts of England a weight of more than ten tons (10,516 kilograms) of dry earth annually passes through their bodies and is brought to the surface on each acre of land, so that the whole superficial bed of vegetable mould passes through their bodies in the course of every few years. From the collapsing of the old burrows, the mold is in constant though slow movement, and the particles composing it are thus rubbed together. Thus the particles of earth, forming the superficial mold, are subjected to conditions eminently favorable for their decomposition and disintegration. This keeps the surface of the earth perfectly suited to the growth of an abundant array of fruits and vegetables.

Worms are poorly provided with sense-organs, for they cannot be said to see, although they can just distinguish between light and darkness; they are completely deaf, and have only a feeble power of smell; the sense of touch alone is well developed. They can, therefore, learn little about the outside world, and it is surprising that they should exhibit some skill in lining their burrows with their castings and with leaves, and in the case of some species in piling up their castings into tower-like constructions. But it is far more surprising that they should apparently exhibit some degree of intelligence instead of a mere blind, instinctive impulse, in their manner of plugging up the mouths of their burrows. They act in nearly the same manner as would a man, who had to close a cylindrical tube with different kinds of leaves, petioles, triangles of paper, etc., for they commonly seize such objects by their pointed ends. But with thin objects a certain number are drawn in by their broader ends. They do not act in the same unvarying manner in all cases, as do most of the lower animals.

The underlined word “unvarying” most nearly means __________.

Possible Answers:

consistent

wondering

creative

inherent

wonderful

Correct answer:

consistent

Explanation:

In context, the author is talking about how worms react to different circumstances, with regard to choosing objects to plug the holes of their burrows by selecting different materials. The worms show some sort of creative judgment which clearly greatly impresses the author. The author says, “They act in nearly the same manner as would a man . . . for they commonly seize such objects by their pointed ends. But with thin objects a certain number are drawn in by their broader ends. They do not act in the same unvarying manner in all cases, as do most of the lower animals.” Here it is clear that “unvarying” means not varying, staying constant and consistent. The worms are “do not act in the same unvarying manner . . . as do most of the lower animals.” Instead the worms are not consistent, able to change based on circumstance. To provide further help, “inherent” means naturally possessed or natural; “wondering” means thinking; and “wonderful” means great and brilliant.

Example Question #41 : Science Passages

Adapted from “Comets” by Camille Flammarion in Wonders of Earth, Sea, and Sky (1902, ed. Edward Singleton Holden)

The history of a comet would be an instructive episode of the great history of the heavens. In it could be brought together the description of the progressive movement of human thought, as well as the astronomical theory of these extraordinary bodies. Let us take, for example, one of the most memorable and best-known comets, and give an outline of its successive passages near the Earth. Like the planetary worlds, comets belong to the solar system, and are subject to the rule of the Star King. It is the universal law of gravitation which guides their path; solar attraction governs them, as it governs the movement of the planets and the small satellites. The chief point of difference between them and the planets is that their orbits are very elongated, and instead of being nearly circular, they take the elliptical form. In consequence of the nature of these orbits, the same comet may approach very near the sun, and afterwards travel from it to immense distances.

Thus, the period of the Comet of 1680 has been estimated at three thousand years. It approaches the sun, so as to be nearer to it than our moon is to us, whilst it recedes to a distance 853 times greater than the distance of the Earth from the sun. On the 17th of December, 1680, it was at its perihelion—that is, at its greatest proximity to the sun; it is now continuing its path beyond the Neptunian orbit. Its velocity varies according to its distance from the solar body. At its perihelion it travels thousands of leagues per minute; at its aphelion it does not pass over more than a few yards.  

Its proximity to the Sun in its passage near that body caused Newton to think that it received a heat twenty-eight thousand times greater than that we experience at the summer solstice, and that this heat being two thousand times greater than that of red-hot iron, an iron globe of the same dimensions would be fifty thousand years entirely losing its heat. Newton added that in the end, comets will approach so near the sun that they will not be able to escape the preponderance of its attraction, and that they will fall one after the other into this brilliant body, thus keeping up the heat which it perpetually pours out into space. Such is the deplorable end assigned to comets by the author of the Principia, an end which makes De la Brétonne say to Rétif: "An immense comet, already larger than Jupiter, was again increased in its path by being blended with six other dying comets. Thus displaced from its ordinary route by these slight shocks, it did not pursue its true elliptical orbit; so that the unfortunate thing was precipitated into the devouring centre of the Sun." "It is said," added he, "that the poor comet, thus burned alive, sent forth dreadful cries!"

The underlined word “aphelion” most likely means __________.

Possible Answers:

Furthest point from the sun

Fasted speed obtained

Closest point to the sun

Slowest speed obtained

Closest point to Earth

Correct answer:

Furthest point from the sun

Explanation:

It is most likely that the words “aphelion” and “perihelion” are words you have never encountered before. However, their meanings can be determined from a close analysis of context. The relevant information is contained in the second paragraph, where the author defines “perihelion” for his readers. He says, "it was at its perihelion—that is, at its greatest proximity to the sun." So, a “perihelion” is the closest point to the sun in the orbit of a comet. From this alone, you could probably infer than an “aphelion” is likely to be the opposite, the furthest point from the sun. But, there is other information to help you figure this out. The author says, “[A comet's] velocity varies according to its distance from the solar body. At its perihelion it travels thousands of leagues per minute; at its aphelion it does not pass over more than a few yards.” So, the speed of a comet changes based on how close to the sun it is; at its “perihelion” or closest point it is very fast, and at its “aphelion” it is very slow. This is enough information to reliably determine that “aphelion” must mean furthest point from the sun.

Example Question #12 : Determining Context Dependent Word Meanings In Science Passages

Adapted from ‘Comets’ by Camille Flammarion in Wonders of Earth, Sea, and Sky (1902) edited by Edward Singleton Holden.

The history of a comet would be an instructive episode of the great history of the heavens. In it could be brought together the description of the progressive movement of human thought, as well as the astronomical theory of these extraordinary bodies. Let us take, for example, one of the most memorable and best-known comets, and give an outline of its successive passages near the Earth. Like the planetary worlds, Comets belong to the solar system, and are subject to the rule of the Star King. It is the universal law of gravitation which guides their path; solar attraction governs them, as it governs the movement of the planets and the small satellites. The chief point of difference between them and the planets is, that their orbits are very elongated; and, instead of being nearly circular, they take the elliptical form. In consequence of the nature of these orbits, the same comet may approach very near the Sun, and afterwards travel from it to immense distances.

Thus, the period of the Comet of 1680 has been estimated at three thousand years. It approaches the Sun, so as to be nearer to it than our Moon is to us, whilst it recedes to a distance 853 times greater than the distance of the Earth from the Sun. On the 17th of December, 1680, it was at its perihelion — that is, at its greatest proximity to the Sun; it is now continuing its path beyond the Neptunian orbit. Its velocity varies according to its distance from the solar body. At its perihelion it travels thousands of leagues per minute; at its aphelion it does not pass over more than a few yards.  

Its proximity to the Sun in its passage near that body caused Newton to think that it received a heat twenty-eight thousand times greater than that we experience at the summer solstice; and that this heat being two thousand times greater than that of red-hot iron, an iron globe of the same dimensions would be fifty thousand years entirely losing its heat. Newton added that in the end comets will approach so near the Sun that they will not be able to escape the preponderance of its attraction, and that they will fall one after the other into this brilliant body, thus keeping up the heat which it perpetually pours out into space. Such is the deplorable end assigned to comets by the author of the "Principia," an end which makes De la Brétonne say to Rétif: "An immense comet, already larger than Jupiter, was again increased in its path by being blended with six other dying comets. Thus displaced from its ordinary route by these slight shocks, it did not pursue its true elliptical orbit; so that the unfortunate thing was precipitated into the devouring centre of the Sun." "It is said," added he, "that the poor comet, thus burned alive, sent forth dreadful cries!"

The underlined word “displaced” most nearly means __________.

Possible Answers:

replaced

disturbed

remained

encouraged

welcomed

Correct answer:

disturbed

Explanation:

In context, you are told that "An immense comet, already larger than Jupiter, was again increased in its path by being blended with six other dying comets. Thus displaced from its ordinary route by these slight shocks, it did not pursue its true elliptical orbit." So, the original comet was affected by six other comets and it therefore did not follow its original orbital pattern. We may therefore say that it was “disturbed” from its position. Most of these answer choices are correct definitions for the word “displaced,” with the exceptions of “welcomed” and “remained," which are loose antonyms. However, “replaced” and “encouraged” do not quite fit with the tone and meaning of the excerpt, certainly not as well as “disturbed” does. Never settle for simply figuring out what you think the word means when answering questions like this; always examine the context—that is, the way the word is used specifically in the passage!

Example Question #1 : Determining Context Dependent Word Meanings In Science Passages

Adapted from "Bats" by W. S. Dallas in A Book of Natural History (1902, ed. David Starr Jordan)

Like the owls, with which they share the dominion of the evening air, the bats have a perfectly noiseless flight; their activity is chiefly during the twilight, although some species are later, and in fact seem to keep up throughout the whole night. As they rest during the day, concealed usually in the most inaccessible places they can find, and are seen only upon the wing, their power of flight is their most striking peculiarity in the popular mind, and it is perhaps no great wonder that by many people, both in ancient and modern times, they have been regarded as birds. Nevertheless, their hairy bodies and leathery wings are so unlike anything that we ordinarily understand as pertaining to a bird, that opinion was apparently always divided, as to the true nature of these creatures—“a mouse with wings,” as Goldsmith called it once, according to James Boswell, is certainly a curious animal, and very difficult to classify so long as the would-be systematist has no particularly definite ideas to guide him. The likeness of the bat to a winged mouse has made itself felt in the name given to the creature in many languages, such as the “chauvesouris” of the French and the “flitter-mouse” of some parts of England, the latter being reproduced almost literally in German, Dutch, and Swedish, while the Danes called the bat a “flogenmues,” which has about the same meaning.

The underlined word “concealed” most nearly means __________.

Possible Answers:

hidden

revealed

flying

feasting

residing

Correct answer:

hidden

Explanation:

In context, the author says, “As they rest during the day, concealed usually in the most inaccessible places they can find, and are seen only upon the wing . . . “ Because the places they are “concealed” in are “inaccessible” (unable to be accessed) and hard to see, we can reasonably conclude that “concealed” probably means hidden, which is indeed the correct answer. To provide further help, “revealed” means shown; “residing” means living; and “feasting” means eating with enthusiasm or in a large group.

Example Question #121 : Science Passages

Adapted from "Bats" by W. S. Dallas in A Book of Natural History (1902, ed. David Starr Jordan)

Like the owls, with which they share the dominion of the evening air, the bats have a perfectly noiseless flight; their activity is chiefly during the twilight, although some species are later, and in fact seem to keep up throughout the whole night. As they rest during the day, concealed usually in the most inaccessible places they can find, and are seen only upon the wing, their power of flight is their most striking peculiarity in the popular mind, and it is perhaps no great wonder that by many people, both in ancient and modern times, they have been regarded as birds. Nevertheless, their hairy bodies and leathery wings are so unlike anything that we ordinarily understand as pertaining to a bird, that opinion was apparently always divided, as to the true nature of these creatures—“a mouse with wings,” as Goldsmith called it once, according to James Boswell, is certainly a curious animal, and very difficult to classify so long as the would-be systematist has no particularly definite ideas to guide him. The likeness of the bat to a winged mouse has made itself felt in the name given to the creature in many languages, such as the “chauvesouris” of the French and the “flitter-mouse” of some parts of England, the latter being reproduced almost literally in German, Dutch, and Swedish, while the Danes called the bat a “flogenmues,” which has about the same meaning.

The underlined word “pertaining” most nearly means __________.

Possible Answers:

underwhelming

seceding

allowing

relating

according

Correct answer:

relating

Explanation:

In context, the author says, "Nevertheless, their hairy bodies and leathery wings are . . .  unlike anything that we ordinarily understand as pertaining to a bird." We know that birds do not have hairy bodies or leathery wings, so we can determine that the author is talking about things that are unlike anything ordinarily “relating” to birds. “Pertaining to” means relating to. To provide further help, “seceding” means breaking away from and “according” means giving or stated by.

Example Question #32 : Science Passages

Adapted from ‘The Man-Like Apes’ by T.H. Huxley in A Book of Natural History (1902) edited by David Starr Jordan.

The Orangutan is found only in Sumatra and Borneo, and is common in either of these islands—in both of which it occurs always in low, flat plains, never in the mountains. It loves the densest and most sombre of the forests, which extend from the seashore inland, and thus is found only in the eastern half of Sumatra, where alone such forests occur, though, occasionally, it strays over to the western side. On the other hand it is generally distributed through Borneo, except in the mountains, or where the population is dense. In favorable places the hunter may, by good fortune, see three or four in a day.

Except in the pairing time, the old males usually live by themselves. The old females and the immature males, on the other hand, are often met with in twos and threes; and the former occasionally have young with them, though the pregnant females usually separate themselves, and sometimes remain apart after they have given birth to their offspring. The young Orangs seem to remain unusually long under their mother’s protection, probably in consequence of their slow growth. While climbing the mother always carries her young against her bosom, the young holding on by the mother’s hair. At what time of life the Orangutan becomes capable of propagation, and how long the females go with young is unknown, but it is probable that they are not adult until they arrive at ten or fifteen years of age. A female which lived for five years at Batavia had not attained one-third the height of the wild females. It is probable that, after reaching adult years, they go on growing, though slowly, and that they live to forty or fifty years. The Dyaks tell of old Orangs which have not only lost all their teeth, but which find it so troublesome to climb that they maintain themselves on windfalls and juicy herbage.

The underlined word “propagation” most nearly means __________.

Possible Answers:

Aggression

Consumption

Selflessness

Reproduction

Foraging

Correct answer:

Reproduction

Explanation:

To understand the most likely meaning of this word, it is best to consider the larger context of the text of which it is a part. In this portion of the passage, the author is discussing the slow growth of orangutans, as well as their child-rearing habits. This suggests that when the author says, “At what time of life the orangutan becomes capable of propagation," he most probably means “at what time they become capable of giving birth” or “reproduction.” This is supported by the larger context of the sentence in which “propagation” appears: “At what time of life the orangutan becomes capable of propagation, and how long the females go with young is unknown, but it is probable that they are not adult until they arrive at ten or fifteen years of age.” The author is talking about when they are “adult” and “how long the females go with young.” All signs point towards “reproduction.” “Reproduction” is the process of generating and having babies. For further help, "foraging" means looking for food when food is not easily found, especially in the wild; “selflessness” is the opposite of being selfish; and “consumption” is eating.

Example Question #51 : Science Passages

Adapted from Volume Four of The Natural History of Animals: The Animal Life of the World in Its Various Aspects and Relations by James Richard Ainsworth Davis (1903)

The examples of protective resemblance so far quoted are mostly permanent adaptations to one particular sort of surrounding. There are, however, numerous animals which possess the power of adjusting their color more or less rapidly so as to harmonize with a changing environment.

Some of the best known of these cases are found among those mammals and birds that inhabit countries more or less covered with snow during a part of the year. A good instance is afforded by the Irish or variable hare, which is chiefly found in Ireland and Scotland. In summer, this looks very much like an ordinary hare, though rather grayer in tint and smaller in size, but in winter it becomes white with the exception of the black tips to the ears. Investigations that have been made on the closely allied American hare seem to show that the phenomenon is due to the growth of new hairs of white hue. 

The common stoat is subject to similar color change in the northern parts of its range. In summer it is of a bright reddish brown color with the exception of the under parts, which are yellowish white, and the end of the tail, which is black. But in winter, the entire coat, save only the tip of the tail, becomes white, and in that condition the animal is known as an ermine. A similar example is afforded by the weasel. The seasonal change in the vegetarian Irish hare is purely of protective character, but in such an actively carnivorous creature as a stoat or weasel, it is aggressive as well, rendering the animal inconspicuous to its prey.

Which of the following terms is closest in meaning to the underlined word “inconspicuous”?

Possible Answers:

wily

hidden

obvious

fraudulent

important

Correct answer:

hidden

Explanation:

The word “inconspicuous” is used the passage’s last sentence, “The seasonal change in the vegetarian Irish hare is purely of protective character, but in such an actively carnivorous creature as a stoat or weasel, it is aggressive as well, rendering the animal inconspicuous to its prey.” “Important” makes no sense in this context, so we can discard that answer. “Wily” (sneaky and clever) and “fraudulent” (deceptive) may each seem like an ok answer, but neither of these would necessarily make the animal a better predator, and “wily” doesn’t describe how a predator would relate to its prey, and “fraudulent” is usually reserved for describing human behavior and intentions. “Hidden” would certainly make the animal a better predator, though—if a predator were “hidden” from its prey, it would be much harder for the prey to avoid the predator. “Hidden” makes the most sense in the context of the sentence, so it is the correct answer.

Example Question #2 : Analyzing Meaning, Purpose, And Effect Of Specified Text In Natural Science Passages

Adapted from “Birds in Retreat” in “Animal Defences—Active Defence” in Volume Four of The Natural History of Animals: The Animal Life of the World in Its Various Aspects and Relations by James Richard Ainsworth Davis (1903)

Among the large running birds are forms, like the African ostrich, in which the absence of powers of flight is largely compensated by the specialization of the legs for the purpose of rapid movement on the ground. For straightforward retreat in open country nothing could be more effective; but another kind of adaptation is required in birds like rails, which are deficient in powers of flight, and yet are able to run through thickly-growing vegetation with such rapidity as to commonly elude their enemies. This is rendered possible by the shape of their bodies, which are relatively narrow and flattened from side to side, so as to easily slip between the stems of grasses, rushes, and similar plants. Anyone who has pursued our native land-rail or corn-crake with intent to capture will have noted how extremely difficult it is even to get within sight of a bird of this sort. 

Certain birds, unfortunately for themselves, have lost the power of flight without correspondingly increased powers of running, and have paid the penalty of extinction. Such an arrangement, as might be anticipated, was the result of evolution in islands devoid of any predatory ground-animals, and a classic example of it is afforded by the dodo and its allies, birds related to the pigeons. The dodo itself was a large and clumsy-looking species that at one time abounded in the island of Mauritius, which, like oceanic islands generally, possessed no native mammals, while its indigenous reptiles were only represented by lizards. The ubiquitous sailor, however, and the animals (especially swine) which he introduced, brought about the extinction of this helpless bird in less than a century after its first discovery in 1598. Its memory is now only kept green by a few contemporary drawings and descriptions, certain museum remains, and the proverb "as extinct as a dodo.” A similar fate must overtake any organism suddenly exposed to new and unfavorable conditions, if devoid of sufficient plasticity to rapidly accommodate itself to the altered environment.

Based on the way in which it is used in the passage, what is the meaning of the underlined word “ubiquitous”?

Possible Answers:

not widely known

careful

brave

traveling everywhere

staying in one place

Correct answer:

traveling everywhere

Explanation:

Even if you don’t know what the word “ubiquitous” means, you can work out its meaning from the way it is used in the passage. “Ubiquitous” is used in the following line in the second paragraph:

“The ubiquitous sailor, however, and the animals (especially swine) which he introduced, brought about the extinction of this helpless bird in less than a century after its first discovery in 1598.”

Let’s consider each of the answer choices. “Staying in one place” doesn’t make sense, as the sailor clearly visited New Zealand. “Careful” doesn’t seem correct in that the sailors brought animals that hurt the indigenous species, and neither “brave” nor “not widely known” are supported at all. The only answer choice that makes sense is “traveling everywhere.” If sailors traveled everywhere, it would make sense that they would travel to New Zealand.

Note: "ubiquitous" is defined as located or existing everywhere, but "traveling everywhere" is in line with the author's use of the term in the passage.

Example Question #31 : Language In Science Passages

Adapted from “The Progress of Medical Education in the United States” in the Scientific American Supplement No. 1157 Vol. XLV (March 5th, 1898)

It is pleasing to note and it augurs well for the future that a decided advance has been made in the direction of a more thorough medical training in America, yet at the same time it is discouraging to observe that, despite these progressive steps, competition does not abate, but rather daily becomes more acute.

There is now a grand total of one hundred and fifty-four medical schools in America. To make a telling comparison, the total number of medical schools in Austria and Germany, with a population exceeding that of this country, is twenty-nine. Great Britain, with more than half the population, has seventeen; while Russia, with one hundred million inhabitants, has nine. Of course we do not argue that America, with her immense territory and scattered population, does not need greater facilities for the study of medicine than do thickly inhabited countries, as Germany and Great Britain; but we do contend that when a city of the size of St. Louis has as many schools as Russia, the craze for multiplying these schools is being carried to absurd and harmful lengths.

However, that the number of schools and their yearly supply of graduates of medicine are far beyond the demand is perfectly well known to all. The Medical Record and other medical journals have fully discussed and insisted upon that point for a considerable time. The real question at issue is by what means to remedy or at least to lessen the bad effects of the system as quickly as possible. 

The first and most important steps toward this desirable consummation have been already taken, and when a four years' course comes into practice throughout the country, the difficult problem of checking excessive competition will at any rate be much nearer its solution. Why should France, Germany, Great Britain and other European nations consider that a course of from five to seven years is not too long to acquire a good knowledge of medical work, while in many parts of America two or three years' training is esteemed ample for the manufacture of a full-fledged doctor? Such methods are unfair both to the public and to the medical profession.

The underlined word “augurs” most nearly means __________.

Possible Answers:

bodes

undermines

examines

rankles

donates

Correct answer:

bodes

Explanation:

The word “augurs” most usually means suggests something good will happen in the future. If you did not know the definition of this word, it would become necessary to try and determine the meaning of the word from context. The author says “It is pleasing to note and it augurs well for the future that a decided advance has been made in the direction of a more thorough medical training." Because it is “pleasing” and because the word is suggesting something will happen in the future, you can reasonably determine that the closest word in meaning is “bodes.” “Bodes” also means suggests something will happen in the future. To provide further help, “undermine” means weaken something or damage the image of, and “rankles” means causes irritation.

Example Question #1 : Analyzing Tone, Style, And Figurative Language In Science Passages

Adapted from On the Origin of Species by Charles Darwin (1859)

How will the struggle for existence, discussed too briefly in the last chapter, act in regard to variation? Can the principle of selection, which we have seen is so potent in the hands of man, apply in nature? I think we shall see that it can act most effectually. Let it be borne in mind in what an endless number of strange peculiarities our domestic productions, and, in a lesser degree, those under nature, vary; and how strong the hereditary tendency is. Under domestication, it may be truly said that the whole organization becomes in some degree plastic. Let it be borne in mind how infinitely complex and close-fitting are the mutual relations of all organic beings to each other and to their physical conditions of life. Can it, then, be thought improbable, seeing that variations useful to man have undoubtedly occurred, that other variations useful in some way to each being in the great and complex battle of life, should sometimes occur in the course of thousands of generations? If such do occur, can we doubt (remembering that many more individuals are born than can possibly survive) that individuals having any advantage, however slight, over others, would have the best chance of surviving and of procreating their kind? On the other hand, we may feel sure that any variation in the least degree injurious would be rigidly destroyed. This preservation of favorable variations and the rejection of injurious variations, I call Natural Selection. Variations neither useful nor injurious would not be affected by natural selection, and would be left a fluctuating element, as perhaps we see in the species called polymorphic.

We shall best understand the probable course of natural selection by taking the case of a country undergoing some physical change, for instance, of climate. The proportional numbers of its inhabitants would almost immediately undergo a change, and some species might become extinct. We may conclude, from what we have seen of the intimate and complex manner in which the inhabitants of each country are bound together, that any change in the numerical proportions of some of the inhabitants, independently of the change of climate itself, would most seriously affect many of the others. If the country were open on its borders, new forms would certainly immigrate, and this also would seriously disturb the relations of some of the former inhabitants. Let it be remembered how powerful the influence of a single introduced tree or mammal has been shown to be. But in the case of an island, or of a country partly surrounded by barriers, into which new and better adapted forms could not freely enter, we should then have places in the economy of nature which would assuredly be better filled up, if some of the original inhabitants were in some manner modified; for, had the area been open to immigration, these same places would have been seized on by intruders. In such case, every slight modification, which in the course of ages chanced to arise, and which in any way favoured the individuals of any of the species, by better adapting them to their altered conditions, would tend to be preserved; and natural selection would thus have free scope for the work of improvement.

The tone of this passage can best be described as __________.

Possible Answers:

informative

abrasive

ill-considered

none of these answers

angry

Correct answer:

informative

Explanation:

The tone of the passage hints at hope for all sorts of species and is quite curious. Darwin does not seem angry or abrasive in this passage, nor angry. Instead, he seems eager to understand what he is studying and explains his ideas clearly.

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