SSAT Middle Level Reading : Science Passages

Study concepts, example questions & explanations for SSAT Middle Level Reading

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Example Questions

Example Question #21 : Making Inferences About The Author Or Natural Science Passage Content

"Cacti" by Ami Dave (2013)

Cacti are plants suited to the desert, and we must always keep this factor in mind when growing ornamental cacti in our gardens, for it helps us provide cacti with conditions that allow them to survive and thrive. For example, a cactus should never be watered over its body, as it will start to rot. This is because it is covered with a waxy coating which prevents water loss through evaporation. When one waters the cactus over its body, the waxy coating is washed away and the plant begins to rot. The amount of water that one must supply to the cactus is very much dependent upon the season and upon the climate of the place. During the summer season one should water cacti every four days, whereas in the rainy season, once every fifteen days is quite enough.

Cacti need a minimum of two and a half hours of sunlight per day; however, they should not be kept in the sun all day because they may wrinkle when exposed to too much bright sunlight. Unlike other plants, cacti produce carbon dioxide during the day and oxygen during the night, so they are ideal plants to be kept in bedrooms to freshen up the air at night.

If a cactus is to thrive and prosper, the size of the pot in which it is grown needs to be monitored carefully. The pot should always be a little smaller than the plant itself because it is only when the plant has to struggle to survive that it will thrive. If the pot is too spacious and the plant does not need to struggle, chances are that the cactus will die. Similarly, if a cactus shows no signs of growth, stop watering it. Watering should be resumed only when the plant begins to grow again.

The substrata of a cactus pot is ideally composed of pieces of broken bricks at the bottom, followed by a layer of charcoal above the bricks, and then coarse sand and pebbles above the charcoal. Leaf mould is the best manure.

Grafting cacti is very simple. A very small piece of the cactus plant should be stuck with tape to the plant that needs grafting. The smaller the piece, the easier it is to graft. To reproduce cacti, one has to simply cut off a piece of the cactus, allow it to dry for a few days, and then place it over the cacti substrate. It will automatically develop roots.

It is very easy to differentiate between cacti and other plants that look like cacti. All cacti have fine hair at the base of each thorn. The so-called “thorns” are in fact highly modified leaves which prevent loss of water through transpiration. If one ever gets pricked by cacti thorns, one should take tape, place it over the area where the thorns have penetrated the skin, and then peel it off. All of the thorns will get stuck to the tape and will be removed.

The passage is most likely an excerpt from what type of document?

Possible Answers:

A manual about how to grow cacti at home

A science textbook

A personal anecdote about cacti 

A descriptive panel at a botanical garden

An informational brochure

Correct answer:

A manual about how to grow cacti at home

Explanation:

It most likely comes from a how-to manual, since it outlines the steps for planting and nurturing a cactus as it grows. A brochure would not contain quite as much information, and would not be detailed. A botanical garden would address the lineage of the plant and more about its genus and species, rather than how to grow it. A science textbook would explore the scientific analysis of the plant, such as how it obtains energy through photosynthesis and more facts along those lines. A personal anecdote about cacti would not need to give any information about how to grow one.

Example Question #1 : Making Inferences In Narrative Science Passages

"Cacti" by Ami Dave (2013)

Cacti are plants suited to the desert, and we must always keep this factor in mind when growing ornamental cacti in our gardens, for it helps us provide cacti with conditions that allow them to survive and thrive. For example, a cactus should never be watered over its body, as it will start to rot. This is because it is covered with a waxy coating which prevents water loss through evaporation. When one waters the cactus over its body, the waxy coating is washed away and the plant begins to rot. The amount of water that one must supply to the cactus is very much dependent upon the season and upon the climate of the place. During the summer season one should water cacti every four days, whereas in the rainy season, once every fifteen days is quite enough.

Cacti need a minimum of two and a half hours of sunlight per day; however, they should not be kept in the sun all day because they may wrinkle when exposed to too much bright sunlight. Unlike other plants, cacti produce carbon dioxide during the day and oxygen during the night, so they are ideal plants to be kept in bedrooms to freshen up the air at night.

If a cactus is to thrive and prosper, the size of the pot in which it is grown needs to be monitored carefully. The pot should always be a little smaller than the plant itself because it is only when the plant has to struggle to survive that it will thrive. If the pot is too spacious and the plant does not need to struggle, chances are that the cactus will die. Similarly, if a cactus shows no signs of growth, stop watering it. Watering should be resumed only when the plant begins to grow again.

The substrata of a cactus pot is ideally composed of pieces of broken bricks at the bottom, followed by a layer of charcoal above the bricks, and then coarse sand and pebbles above the charcoal. Leaf mould is the best manure.

Grafting cacti is very simple. A very small piece of the cactus plant should be stuck with tape to the plant that needs grafting. The smaller the piece, the easier it is to graft. To reproduce cacti, one has to simply cut off a piece of the cactus, allow it to dry for a few days, and then place it over the cacti substrate. It will automatically develop roots.

It is very easy to differentiate between cacti and other plants that look like cacti. All cacti have fine hair at the base of each thorn. The so-called “thorns” are in fact highly modified leaves which prevent loss of water through transpiration. If one ever gets pricked by cacti thorns, one should take tape, place it over the area where the thorns have penetrated the skin, and then peel it off. All of the thorns will get stuck to the tape and will be removed.

Which of the following can be inferred from the information provided in the passage?

Possible Answers:

Cacti follow a respiration cycle that is different than that of other plants.

Pot size is not an important factor in cactus growth.

It is difficult to distinguish cacti from other plants.

People have been growing cacti in their homes for hundreds of years.

Cacti are found in every desert known to man.

Correct answer:

Cacti follow a respiration cycle that is different than that of other plants.

Explanation:

The second paragraph states that, unlike other plants, cacti produce CO2 during the day and O2 during the night, making them good plants to freshen the air when one is sleeping. Thus, it can be inferred that cacti have a unique respiration cycle, compared to other plants. The other answer choices are not inferences that can be made from the passage. The passage states that pot size is indeed a factor is growth, and the last paragraph mentions how it is easy to tell cacti apart from other plants. While the passage does mention that the cactus is a desert plant, nowhere does it say that cacti are found in EVERY desert. Similarly, the passage provides no information about for how long people have been growing cacti in their homes.

Example Question #221 : Isee Upper Level (Grades 9 12) Reading Comprehension

Adapted from "The Man-Like Apes" by T. H. Huxley in A Book of Natural History (1902, ed. 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 that 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 “Dyaks” are most probably __________.

Possible Answers:

Biologists who study the behavior of orangutans

Settlers from Europe who live in Borneo and Sumatra

Indigenous people of Borneo or Sumatra

Scientists who assist the work of the author

Science fiction writers who incorporate orangutans into their stories

Correct answer:

Indigenous people of Borneo or Sumatra

Explanation:

In context, the author says “The Dyaks tell of old orangs that 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 excerpt suggests that some people, called the “Dyaks,” have some sort of lengthy experience and knowledge of the behavior and lifetimes of orangutans, suggesting deep familiarity with these creatures. From this you can infer that “Dyaks” are most probably “indigenous people of Borneo or Sumatra.” And, indeed, this is a name given to a group of indigenous people from Borneo.

Example Question #1 : Making Inferences And Predictions In Science Passages

Adapted from "Birds’ Nests" by John Burroughs in A Book of Natural History (1902, ed. David Starr Jordan)

The woodpeckers all build in about the same manner, excavating the trunk or branch of a decayed tree, and depositing the eggs on the fine fragments of wood at the bottom of the cavity. Though the nest is not especially an artistic work, requiring strength rather than skill, yet the eggs and the young of few other birds are so completely housed from the elements, or protected from their natural enemies—the jays, crows, hawks, and owls. A tree with a natural cavity is never selected, but one which has been dead just long enough to have become soft and brittle throughout. The bird goes in horizontally for a few inches, making a hole perfectly round and smooth and adapted to his size, then turns downward, gradually enlarging the hole, as he proceeds, to the depth of ten, fifteen, twenty inches, according to the softness of the tree and the urgency of the mother bird to deposit her eggs. While excavating, male and female work alternately. After one has been engaged fifteen or twenty minutes, drilling and carrying out chips, it ascends to an upper limb, utters a loud call or two, when its mate soon appears, and, alighting near it on the branch, the pair chatter and caress a moment; then the fresh one enters the cavity and the other flies away.

What can you infer about male and female woodpeckers from this passage?

Possible Answers:

They work quickly and hastily.

They are incapable of showing emotion.

They have a close and intimate bond.

They do not always work together very well.

They mate for life.

Correct answer:

They have a close and intimate bond.

Explanation:

In the concluding lines of this passage, the author talks about how “while excavating, male and female work alternately.” He also says, “the pair chatter and caress a moment; then the fresh one enters the cavity and the other flies away.” The key word for answering this question is “caress.” It means touch and stroke with affection. From the sum of this information, you can reasonably infer that woodpeckers “have a close and intimate bond.”

Example Question #11 : Inferences And Predictions In Narrative Science Passages

Adapted from "How Animals Spend the Winter" by W. S. Blatchley in A Book of Natural History (1902, ed. David Starr Jordan)

One of the greatest problems that each of the living forms about us has had to solve, during the years of its existence on earth, is how best to perpetuate its kind during that cold season that once each year, in our temperate zone, is bound to come. Many are the solutions to this problem. Each form of life has, as it were, solved it best to suit its own peculiar case, and to the earnest student of Nature there is nothing more interesting than to pry into these solutions and note how varied, strange, and wonderful they are.

To fully appreciate some of the facts mentioned below it must be borne in mind that there is no such thing as “spontaneous generation” of life. Every cell is the offspring of a pre-existing cell. Hence every weed that next season will spring up and provoke the farmer’s ire, and every insect that will then make life almost intolerable for man or beast, exists throughout the winter in some form.

Beginning with the earthworms and their kindred, we find that at the approach of winter they burrow deep down where the icy breath of the frost never reaches, and there they live, during the cold season, a life of comparative quiet. That they are exceedingly sensitive to warmth, however, may be proven by the fact that when a warm rain comes some night in February or March, thawing out the crust of the earth, the next morning reveals in our dooryards the mouths of hundreds of the pits or burrows of these primitive tillers of the soil, each surrounded by a little pile of pellets, the castings of the active artisans of the pits during the night before.

If we will get up before dawn on such a morning we can find the worms crawling actively about over the surface of the ground, but when the first signs of day appear they seek once more their protective burrows, and only an occasional belated individual serves as a breakfast for the early birds.

Which of these can you most reasonably infer about this passage?

Possible Answers:

It is part of a longer debate about the nature of life.

It is written by a dedicated lover of earthworms.

It has been translated from another language.

It was written by an American.

It is part of a longer passage about the same subject.

Correct answer:

It is part of a longer passage about the same subject.

Explanation:

It is very difficult to make any inferences of these kinds from this passage. Although the author talks about earthworms a lot, there is nothing to suggest he could be described as a “dedicated lover of earthworms.” There is also no evidence to suggest this was written in another language, nor by an American. However, there is one small piece of evidence that tells you this is almost certainly part of a longer passage about the same subject. When transitioning from the manner in which animals are able to survive the winter to a specific example of the earthworm, the author suggests that the earthworm is going to be the first of many examples. He says “Beginning with the earthworms and their kindred." The key word here is “beginning.” If he were just to talk about earthworms it would become a redundant phrase, and because in this excerpt he only talks about earthworms, we can infer this is part of a longer passage. The idea that it is part of a debate about the nature of life requires further inference because although the essay is somewhat persuasive in nature, it does not specifically refute any points.

Example Question #81 : Narrative Science Passages

Adapted from "The Greatest Sea-Wave Ever Known" by R. A. Proctor in Wonders of Earth, Sea, and Sky (1902, ed. Edward Singleton Holden)

It was at Arequipa, at the foot of the lofty volcanic mountain Misti, that the most terrible effects of the great earthquake were experienced. Within historic times, Misti has poured forth no lava streams, but that the volcano is not extinct is clearly evidenced by the fact that in 1542 an enormous mass of dust and ashes was vomited forth from its crater. On August 13th, 1868, Misti showed no signs of being disturbed. So far as the volcanic neighbor was concerned, the forty-four thousand inhabitants of Arequipa had no reason to anticipate the catastrophe which presently befell them.

At five minutes past five, an earthquake shock was experienced, which, though severe, seems to have worked little mischief. Half a minute later, however, a terrible noise was heard beneath the earth; a second shock more violent than the first was felt, and then began a swaying motion, gradually increasing in intensity. In the course of the first minute, this motion had become so violent that the inhabitants ran in terror out of their houses into the streets and squares. In the next two minutes, the swaying movement had so increased that the more lightly built houses were cast to the ground, and the flying people could scarcely keep their feet. "And now," says Von Tschudi, "there followed during two or three minutes a terrible scene. The swaying motion changed into fierce vertical upheaval. The subterranean roaring increased in the most terrifying manner; then were heard the heart-piercing shrieks of the wretched people, the bursting of walls, the crashing fall of houses and churches, while over all rolled thick clouds of a yellowish-black dust, which, had they been poured forth many minutes longer, would have suffocated thousands." Although the shocks had lasted but a few minutes, the whole town was destroyed. Not one building remained uninjured, and there were few that did not lie in shapeless heaps of ruins.

What can be reasonably inferred about Von Tschudi?

Possible Answers:

He is a considered an expert on the disaster at Arequipa.

He was born and raised in Arequipa.

He holds opinions and conclusions about the disaster with which the author strongly disagrees.

He was living in Arequipa at the time of the eruption.

He is a noted literary figure.

Correct answer:

He is a considered an expert on the disaster at Arequipa.

Explanation:

When describing the immediate effects and impact of the volcanic eruption, the author of this passage turns to Von Tschudi’s description of events. This should suggest to us two things: firstly, that the author is not an expert on the situation and is writing about this eruption as an introduction to something else. Also, and more importantly, it should suggest that Von Tschudi is “considered an expert on the disaster at Arequipa.” If his analysis is being quoted in another scholarly paper, he must be thought of as an expert. It might be reasonably to infer, from Von Tschudi’s thorough description, that he was living in Arequipa at the time or was born and raised there; however, there is insufficient evidence to reliably determine this. Answering with these two answers requires a good deal more inference than the correct answer.

Example Question #81 : 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!"

Who can you infer is the author of Principia?

Possible Answers:

Newton

There is not enough information to say

De la Brétonne

Rétif

The author of this passage

Correct answer:

Newton

Explanation:

Contextual clues in the third paragraph should help you determine that the author of the Principia is “Newton.” The author of this passage says “Such is the deplorable end assigned to comets by the author of the Principia," and he says this immediately after a long discussion of the research and conclusions reached by Newton on the demise of the very large comet under discussion throughout the passage. The key here is to identify the correct clues, and ignore the confusing mention of “De la Brétonne” and “Rétif” immediately after the mention of the Principia.

Example Question #1 : Drawing Conclusions In Science Passages

Adapted from A Catechism of Familiar Things: Their History and the Events Which Led to Their Discovery by the Benziger Brothers (1881)

Potatoes grew wild in Peru, a country of South America, from where they were transplanted to other parts of the American continent, and afterwards to Europe. The honor of introducing this useful vegetable into England is divided between Sir Francis Drake, in 1580, and Sir Walter Raleigh, in 1586, some crediting it to the former, and others to the latter. It is certain they were obtained from Virginia in the time of Raleigh; they were grown only in the gardens of the nobility, and were considered a great delicacy. They now constitute a crucial article of food in most of the countries of Europe and America; in Ireland, they have long furnished nearly four-fifths of the entire food of the people.

What might we determine about the significance of the potato in Irish history?

Possible Answers:

It led to widespread famine and disease.

It was encouraged by the British so that they could monopolize the more expensive produce.

It fed a large percentage of the population for a long time.

It was used as currency in the era before standardized money.

It increased relations between the Irish and the New World.

Correct answer:

It fed a large percentage of the population for a long time.

Explanation:

Many of these answer choices are in fact true, but only one is supported by the information included in this passage. The correct answer is that the potato “fed a large percentage of the population for a long time.” This is shown by the author when he says, “in Ireland, they have long furnished nearly four-fifths of the entire food of the people.” “Furnished,” in this context, means provided for.

Example Question #11 : Making Inferences In Narrative Science Passages

Adapted from "Wasps" by Thomas G. Belt in A Book of Natural History (1902, ed. David Starr Jordan)

One day I saw a small black and yellow banded wasp hunting for spiders; it approached a web where a spider was stationed in the center, made a dart towards it—apparently a feint to frighten the spider clear of its web; at any rate it had that effect, for it fell to the ground, and was immediately seized by the wasp, who stung it, then ran quickly backwards, dragging the spider after it, up a branch reaching to the ground until it got high enough, when it flew heavily off with it. It was so small, and the spider so cumbersome, that it probably could not have raised it from the ground by flight.

All over the world there are wasps that store their nests with the bodies of spiders for their young to feed on. In Australia, I often witnessed a wasp engaging with a large flat spider that is found on the bark of trees. It would fall to the ground, and lie on its back, so as to be able to grapple with its opponent; but the wasp was always the victor in the encounters I saw, although it was not always allowed to carry off its prey in peace. One day, sitting on the sandbanks on the coast of Hobson’s Bay, I saw one dragging along a large spider. Three or four inches above it hovered two minute flies, keeping a little behind, and advancing with it. The wasp seemed much disturbed by the presence of the tiny flies, and twice left its prey to fly up towards them, but they darted away with it. As soon as the wasp returned to the spider, there they were hovering over and following it again. At last, unable to drive away its small provocateurs, the wasp reached its burrow and took down the spider, and the two flies stationed themselves one on each side of the entrance, and would, doubtless, when the wasp went away to seek another victim, descend and lay their own eggs in the nest.

Which of these inferences about the author can be most easily assumed?

Possible Answers:

He has recently graduated from university after studying entomology, the study of insects.

He is not used to writing about his research.

He lives in Australia.

He is more interested by the behavior of spiders than that of wasps.

He has observed the behavior of wasps around the world.

Correct answer:

He has observed the behavior of wasps around the world.

Explanation:

There is no evidence to support any of these inferences except the one that suggests that the author has “observed the behavior of wasps around the world.” The author says “All over the world there are wasps that store their nests with the bodies of spiders for their young to feed on.” Seeing as he cites no one else's research, it is reasonable to infer that he has conducted this research himself. Although he only mentions his time in Australia, it is unreasonable to conclude that this necessarily means he lives in Australia—he might have only been visiting to conduct research.

Example Question #11 : Making Inferences In Narrative Science Passages

Adapted from "Birds’ Nests" by John Burroughs in A Book of Natural History (1902, ed. David Starr Jordan)

The rarest of all nests is that of the eagle, because the eagle is the rarest of all birds. Indeed, so seldom is the eagle seen, that its presence always seems accidental. It appears as if merely pausing on the way, while bound for some distant unknown region. One September, while a youth, I saw the ring-tailed eagle, an immense bird, the sight of which filled me with awe. It lingered about the hills for two days. Some young cattle, a two year-old colt, and half a dozen sheep were at pasture on a high ridge that led up to the mountain, and in plain view of the house. On the second day, this dusky monarch was seen flying about above them. Presently he began to hover over them, after the manner of a hawk watching for mice. He then with extended legs let himself slowly down upon them, actually grappling the backs of the young cattle, and frightening the creatures so that they rushed about the field in great consternation; and finally, as he grew bolder and more frequent in his descents, the whole herd broke over the fence, and came tearing down to the house “like mad.” It did not seem to be an assault with intent to kill, but was, perhaps, a stratagem resorted to in order to separate the herd and expose the lambs, which hugged the cattle very closely. When he occasionally alighted upon the oaks that stood near, the branch could be seen to sway and bend beneath him. Finally, as a rifleman started out in pursuit of him, he launched into the air, set his wings, and sailed away southward. A few years afterward, in January, another eagle passed through the same locality, alighting in a field near some dead animal, but tarried briefly.

What can you most reasonably infer about the author?

Possible Answers:

He has never written professionally before.

He has a distinct fear of riflemen.

He is a natural woodsman.

He is an avid bird watcher.

He is not religious.

Correct answer:

He is an avid bird watcher.

Explanation:

You can reasonably infer that the author is “an avid bird watcher.” This is because he seems familiar with the specific type of eagles that he has observed, and also because he is out and about wandering around frequently enough to observe and carefully track two eagles. He also seems to know, from experience, that eagles are the rarest of all birds. There is nothing to suggest he is “not religious,” or is writing for the first time. Its possible he is “a natural woodsman,” but requires a great deal more inference than the correct answer. The idea that he has a “fear of riflemen” is not supported by the text.

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