Human anatomy is the scientific study of the body’s structures. Some of these structures are very small and can only be observed and analyzed with the assistance of a microscope. Other larger structures can readily be seen, manipulated, measured, and weighed. The word “anatomy” comes from a Greek root that means “to cut apart.” Human anatomy was first studied by observing the exterior of the body and observing the wounds of soldiers and other injuries. Later, physicians were allowed to dissect bodies of the dead to augment their knowledge. When a body is dissected, its structures are cut apart in order to observe their physical attributes and their relationships to one another. Dissection is still used in medical schools, anatomy courses, and in pathology labs.
Q. Which of the following is true about human anatomy?
B is correct because the other 3 options are all untrue – they each contain at least a word that changes its original meaning. The passage states “Human anatomy was first studied by observing the exterior of the body and observing the wounds of soldiers…”. While the words “human anatomy” are mentioned a few times, the answer can be found by searching for other keywords like “soldiers’” and “wounds”.
The Nature Of Astronomy
Astronomy is defined as the study of the objects that lie beyond our planet Earth and the processes by which these objects interact with one another. We will see, though, that it is much more. It is also humanity’s attempt to organize what we learn into a clear history of the universe, from the instant of its birth in the Big Bang to the present moment.
In considering the history of the universe, we will see again and again that the cosmos evolves; it changes in profound ways over long periods of time. For example, the universe made the carbon, the calcium, and the oxygen necessary to construct something as interesting and complicated as you. Today, many billions of years later, the universe has evolved into a more hospitable place for life. Tracing the evolutionary processes that continue to shape the universe is one of the most important (and satisfying) parts of modern astronomy.
Q. According to paragraph 2, the following is one of the most significant areas of astronomy:
C is correct because it uses synonyms as well as keywords that match passage text whereas option a and d are not mentioned as specific areas of astronomy. Lastly, option b partially mentioned though it’s not explicitly said to be an area of astronomy.
Cold War Terminology
Cold War terminology was developed during the Cold War era (1945–1980). Familiar and still used by many, it involves classifying countries into first world, second world, and third world nations based on respective economic development and standards of living. When this nomenclature was developed, capitalistic democracies such as the U.S. and Japan were considered part of the first world. The poorest, most undeveloped countries were referred to as the third world and included most of sub- Saharan Africa, Latin America, and Asia. The second world was the in-between category: nations not as limited in development as the third world, but not as well off as the first world, having moderate economies and standard of living, such as China or Cuba. Later, sociologist Manual Castells added the term fourth world to refer to stigmatized minority groups that were denied a political voice all over the globe (indigenous minority populations, prisoners, and the homeless, for example).
Q. According to the paragraph, which of the following is true about the U.S. and Japan?
D is correct because when we look for the keywords from the question in the passage, the sentence that contains the “the U.S. and Japan” explains how they were considered first world countries. Since they are not mentioned again, there is no need to look further.
Tissue and Aging
According to poet Ralph Waldo Emerson, “The surest poison is time.” In fact, biology confirms that many functions of the body decline with age. All the cells, tissues, and organs are affected by senescence (the process of deterioration) with noticeable variability between individuals owing to different genetic makeup and lifestyles. The outward signs of aging are easily recognizable. The skin and other tissues become thinner and drier, reducing their elasticity, contributing to wrinkles and high blood pressure. Hair turns gray because follicles produce less melanin, the brown pigment of hair and the iris of the eye. The face looks flabby because elastic and collagen fibers decrease in connective tissue and muscle tone is lost. Glasses and hearing aids may become parts of life as the senses slowly deteriorate, all due to reduced elasticity. Overall height decreases as the bones lose calcium and other minerals. With age, fluid decreases in the fibrous cartilage disks intercalated between the vertebrae in the spine. Joints lose cartilage and stiffen. Many tissues, including those in muscles, lose mass through a process called atrophy. Lumps and rigidity become more widespread. As a consequence, the passageways, blood vessels, and airways become more rigid. The brain and spinal cord lose mass. Nerves do not transmit impulses with the same speed and frequency as in the past. Some loss of thought clarity and memory can accompany aging. More severe problems are not necessarily associated with the aging process and may be symptoms of underlying illness. As exterior signs of aging increase, so do the interior signs, which are not as noticeable.
Q. What does the author say about wrinkles?
B is correct because the keyword in the question – “wrinkles” – is found in the passage in a sentence that explains what is summarized in option b. While half of option a is true, the second half is not – wrinkles are not caused by high blood pressure but rather both are caused by reduced elasticity. Options c and d are simply untrue.
Atomic Theory through the Nineteenth Century
The earliest recorded discussion of the basic structure of matter comes from ancient Greek philosophers, the scientists of their day. In the fifth century BC, Leucippus and Democritus argued that all matter was composed of small, finite particles that they called atomos, a term derived from the Greek word for “indivisible.” They thought of atoms as moving particles that differed in shape and size, and which could join together. Later, Aristotle and others came to the conclusion that matter consisted of various combinations of the four “elements”—fire, earth, air, and water—and could be infinitely divided. Interestingly, these philosophers thought about atoms and “elements” as philosophical concepts, but apparently never considered performing experiments to test their ideas.
The Aristotelian view of the composition of matter held sway for over two thousand years, until English schoolteacher John Dalton helped to revolutionize chemistry with his hypothesis that the behavior of matter could be explained using an atomic theory.
Q. According to paragraph 1, what did some Greek philosophers believe about matter?
C is correct because if we look within the first couple sentences of the keywords in the question – “Greek philosophers” and “matter” – we can find exactly what they “argued” about matter. While the keywords from answer a – “differed”, “size”, and “shape” are in the next sentence, the subject is “particles”, not matter. Option b uses the wrong modifier, “infinite” and “visible”, and option d is a more modern hypothesis by schoolteacher John Dalton.
Fixed and Wandering Stars
Ancient Babylonian, Assyrian, and Egyptian astronomers knew the approximate length of the year. The Egyptians of 3000 years ago, for example, adopted a calendar based on a 365-day year. They kept careful track of the rising time of the bright star Sirius in the predawn sky, which has a yearly cycle that corresponded with the flooding of the Nile River. The Chinese also had a working calendar; they determined the length of the year at about the same time as the Egyptians. The Chinese also recorded comets, bright meteors, and dark spots on the Sun. Later, Chinese astronomers kept careful records of “guest stars”—those that are normally too faint to see but suddenly flare up to become visible to the unaided eye for a few weeks or months. We still use some of these records in studying stars that exploded a long time ago.
The Mayan culture in Mexico and Central America developed a sophisticated calendar based on the planet Venus, and they made astronomical observations from sites dedicated to this purpose a thousand years ago. The Polynesians learned to navigate by the stars over hundreds of kilometers of open ocean—a skill that enabled them to colonize new islands far away from where they began.
In Britain, before the widespread use of writing, ancient people used stones to keep track of the motions of the Sun and Moon. We still find some of the great stone circles they built for this purpose, dating from as far back as 2800 BCE. The best known of these is Stonehenge.
Q. What does the author say about ancient calendars in paragraph 2?
A is correct because, in paragraph 2, the author talks about how the Mayan culture, an ancient group, developed calendars based on Venus – a planet – and “astronomical observations from sites…a thousand years ago”. Thus, we can conclude it’s ancient. Additionally, it says that the Polynesians, another ancient culture, used the stars to navigate. Some of the keywords from option a – “based on” and “planet” – are found within the same sentence in which the question keyword “calendars” is mentioned, thus there is no need to go beyond option a.
The Invention of the X-Ray
German physicist Wilhelm Röntgen (1845–1923) was experimenting with electrical current when he discovered that a mysterious and invisible “ray” would pass through his flesh but leave an outline of his bones on a screen coated with a metal compound. In 1895, Röntgen made the first durable record of the internal parts of a living human: an “X-ray” image (as it came to be called) of his wife’s hand. Scientists around the world quickly began their own experiments with X-rays, and by 1900, X-rays were widely used to detect a variety of injuries and diseases. In 1901, Röntgen was awarded the first Nobel Prize for physics for his work in this field. The X-ray is a form of high energy electromagnetic radiation with a short wavelength capable of penetrating solids and ionizing gases. As they are used in medicine, X-rays are emitted from an X-ray machine and directed toward a specially treated metallic plate placed behind the patient’s body. The beam of radiation results in darkening of the X-ray plate. X-rays are slightly impeded by soft tissues, which show up as gray on the X-ray plate, whereas hard tissues, such as bone, largely block the rays, producing a light-toned “shadow.” Thus, X-rays are best used to visualize hard body structures such as teeth and bones. Like many forms of high energy radiation, however, X- rays are capable of damaging cells and initiating changes that can lead to cancer. This danger of excessive exposure to X-rays was not fully appreciated for many years after their widespread use.
1. The paragraph states that x-rays…
B is correct because we can immediately eliminate option a as it was a male scientist, not a female. A sentence with some of the keywords in option b – “diseases”, “injuries”, and “1900’s” – is in the passage and is true. Like most answers, it is restated using synonyms. Options c and d contain modifiers that might signal to us that they are wrong as well as other words that greatly change the meaning from the passage.
The ninth century gave rise to feudal societies. These societies contained a strict hierarchical system of power based around land ownership and protection. The nobility, known as lords, placed vassals in charge of pieces of land. In return for the resources that the land provided, vassals promised to fight for their lords.
These individual pieces of land, known as fiefdoms, were cultivated by the lower class. In return for maintaining the land, peasants were guaranteed a place to live and protection from outside enemies. Power was handed down through family lines, with peasant families serving lords for generations and generations. Ultimately, the social and economic system of feudalism would fail, replaced by capitalism and the technological advances of the industrial era.
Q. Which of the following best describes a feudal society?
C is correct because option a is incorrect – peasants did not govern the land while option b is vague and does not actually describe how the system worked. Keywords cannot be relied on to find the answer in this question. It also requires reading most of the passage, or at least all of the second paragraph. For, it explains that the lower class or “peasants” cultivated the land. While option d might seem right, it was not a “lineage based system” but rather a system based on land ownership.
Exercise and Bone Tissue
During long space missions, astronauts can lose approximately 1 to 2 percent of their bone mass per month. This loss of bone mass is thought to be caused by the lack of mechanical stress on astronauts’ bones due to the low gravitational forces in space. Lack of mechanical stress causes bones to lose mineral salts and collagen fibers, and thus strength. Similarly, mechanical stress stimulates the deposition of mineral salts and collagen fibers. The internal and external structure of a bone will change as stress increases or decreases so that the bone is an ideal size and weight for the amount of activity it endures. That is why people who exercise regularly have thicker bones than people who are more sedentary. It is also why a broken bone in a cast atrophies while its contralateral mate maintains its concentration of mineral salts and collagen fibers. The bones undergo remodeling as a result of forces (or lack of forces) placed on them.
Q. What does the author say about bones?
A is correct because the final sentence states that bones experience “remodeling” or “changes” based on the “forces or lack of forces” – which is also referred to as mechanical stress in the paragraph – put on them. For this question and answer, it is necessary to read most of the passage because the keyword “bones” from the question is mentioned several times throughout. Since the keywords in option a are spaced out throughout the paragraph also, it might be necessary to go on to options b,c, and d and eliminate incorrect choices first. Option b has some keywords that help us located the sentence quickly – “1-2 percent” and “mass” – but the answer does not match what is written in the paragraph. For, it says “astronauts can lose 1- 2 percent…per month,” not that they do every month. Options c and d are untrue; the actual facts can be found by searching for the keywords “size”, “weight” and “thicker”.
The best-documented large impact took place 65 million years ago, at the end of what is now called the Cretaceous period of geological history. This time in the history of life on Earth was marked by a mass extinction, in which more than half of the species on our planet died out. There are a dozen or more mass extinctions in the geological record, but this particular event (nicknamed the “great dying”) has always intrigued paleontologists because it marks the end of the dinosaur age. For tens of millions of years these great creatures had flourished and dominated. Then, they suddenly disappeared, and thereafter mammals began the development and diversification that ultimately led to all of us.
The object that collided with Earth at the end of the Cretaceous period struck a shallow sea in what is now the Yucatán peninsula of Mexico. Its mass must have been more than a trillion tons, determined from study of a worldwide layer of sediment deposited from the dust cloud that enveloped the planet after its impact. First identified in 1979, this sediment layer is rich in the rare metal iridium and other elements that are relatively abundant in asteroids and comets, but exceedingly rare in Earth’s crust. Even though it was diluted by the material that the explosion excavated from the surface of Earth, this cosmic component can still be identified. In addition, this layer of sediment contains many minerals characteristic of the temperatures and pressures of a gigantic explosion.
Q. According to paragraph 1, which of the following is true?
C is correct because we can find the original sentence in the first paragraph by searching for the keywords – “geological record” and “mass extinctions”. A dozen means 12, and the sentence states that “a dozen or more” which is equivalent to saying “at least 12”. Option a is incorrect because it says “less than 12”, and option b is wrong because it has an incorrect modifier making an absolute statement – “the largest” – when the passage actually uses the word “large”.
Deafness is the partial or complete inability to hear. Some people are born deaf, which is known as congenital deafness. Many others begin to suffer from conductive hearing loss because of age, genetic predisposition, or environmental effects, including exposure to extreme noise (noise-induced hearing loss), certain illnesses (such as measles or mumps), or damage due to toxins (such as those found in certain solvents and metals).
Given the mechanical nature by which the sound wave stimulus is transmitted from the eardrum through the ossicles to the oval window of the cochlea, some degree of hearing loss is inevitable. With conductive hearing loss, hearing problems are associated with a failure in the vibration of the eardrum and/or movement of the ossicles. These problems are often dealt with through devices like hearing aids that amplify incoming sound waves to make vibration of the eardrum and movement of the ossicles more likely to occur.
When the hearing problem is associated with a failure to transmit neural signals from the cochlea to the brain, it is called sensorineural hearing loss. One disease that results in sensorineural hearing loss is Ménière’s disease. Although not well understood, Ménière’s disease results in a degeneration of inner ear structures that can lead to hearing loss, tinnitus (constant ringing or buzzing), vertigo (a sense of spinning), and an increase in pressure within the inner ear. This kind of loss cannot be treated with hearing aids, but some individuals might be candidates for a cochlear implant as a treatment option. Cochlear implants are electronic devices that consist of a microphone, a speech processor, and an electrode array. The device receives incoming sound information and directly stimulates the auditory nerve to transmit information to the brain.
Q. Which of the following best describes conductive hearing loss?
C is correct because it best describes conductive hearing loss. The keywords from option c can be found in paragraph 2 – “inevitable”, “loss”, “problems”, and “eardrum”. The question asks about a specific term in the passage; it is mentioned in more than one paragraph so it is necessary to read at least the first two paragraphs. Option a is incorrect because it is describing deafness. Option b is referring to deafness, which some people can be born with, and option d partly describes how hearing aids work, which is not what the question is asking.
The Ideal Gas Law
During the seventeenth and especially eighteenth centuries, driven both by a desire to understand nature and a quest to make balloons in which they could fly, a number of scientists established the relationships between the macroscopic physical properties of gases, that is, pressure, volume, temperature, and amount of gas. Although their measurements were not precise by today’s standards, they were able to determine the mathematical relationships between pairs of these variables (e.g., pressure and temperature, pressure and volume) that hold for an ideal gas—a hypothetical construct that real gases approximate under certain conditions. Eventually, these individual laws were combined into a single equation—the ideal gas law—that relates gas quantities for gases and is quite accurate for low pressures and moderate temperatures.
1. According to the paragraph, what occurred between the 1600’s and 1700’s?
B is correct because we find the keywords “scientists”, “physical”, “gases”, and in this case, “between” in first and same sentence in which the question keywords are mentioned. Note that the question uses the numerical form of the dates mentioned in the paragraph, i.e., 1600’s and 1700’s is the equivalent to the “seventeenth and… eighteenth centuries”. Option a does match some of the keywords in the same sentence as the correct option, but it doesn’t state that scientists constructed a hypothesis about gas, pressure, volume, and temperature. Options c and d are incorrect as they use additional or incorrect modifiers like “precise” and “small”.
Forensic psychology is a branch of psychology that deals questions of psychology as they arise in the context of the justice system. For example, forensic psychologists (and forensic psychiatrists) will assess a person’s competency to stand trial, assess the state of mind of a defendant, act as consultants on child custody cases, consult on sentencing and treatment recommendations, and advise on issues such as eyewitness testimony and children’s testimony. In these capacities, they will typically act as expert witnesses, called by either side in a court case to provide their research- or experience- based opinions. As expert witnesses, forensic psychologists must have a good understanding of the law and provide information in the context of the legal system rather than just within the realm of psychology. Forensic psychologists are also used in the jury selection process and witness preparation. They may also be involved in providing psychological treatment within the criminal justice system. Criminal profilers are a relatively small proportion of psychologists that act as consultants to law enforcement.
Q. Which of the follow****ing is true about the role of forensic psychologists according to the paragraph?
D is correct because the first three options are incorrect. Option a is technically true, but it’s not the only role that is mentioned in the passage. Option b is untrue and option c uses an incorrect modifier – “most”. Option d mentions all the “various roles” they play, and though the words are in alternate forms, they are still present in the paragraph – “consulting”, “advising”, and “expert witnesses”. B is incorrect because of the difference between the word “expert” and the phrase in the passage “good understanding”.
Cognition and Latent Learning
Although strict behaviorists such as Skinner and Watson refused to believe that cognition (such as thoughts and expectations) plays a role in learning, another behaviorist, Edward C. Tolman, had a different opinion. Tolman’s experiments with rats demonstrated that organisms can learn even if they do not receive immediate reinforcement. This finding was in conflict with the prevailing idea at the time that reinforcement must be immediate in order for learning to occur, thus suggesting a cognitive aspect to learning.
In the experiments, Tolman placed hungry rats in a maze with no reward for finding their way through it. He also studied a comparison group that was rewarded with food at the end of the maze. As the unreinforced rats explored the maze, they developed a cognitive map: a mental picture of the layout of the maze. After 10 sessions in the maze without reinforcement, food was placed in a goal box at the end of the maze. As soon as the rats became aware of the food, they were able to find their way through the maze quickly, just as quickly as the comparison group, which had been rewarded with food all along. This is known as latent learning: learning that occurs but is not observable in behavior until there is a reason to demonstrate it.
Q. According to paragraph 2, which of the following best describes latent learning?
D is correct because it is a reiteration of the final statement about latent learning; it uses synonyms but does include a couple keywords – “learning” and “reason”. Option a is not mentioned at all; the passage talks about experiments not “experimentation” or “hands on” activities. Option b does not describe latent learning and option c contains variations of some of the words in the passage in relation to latent learning (“demonstration”, “reason”) but, overall, the sentence is actually the opposite of the correct answer.
The Process of Aging
As human beings grow older, they go through different phases or stages of life. It is helpful to understand aging in the context of these phases. A life course is the period from birth to death, including a sequence of predictable life events such as physical maturation. Each phase comes with different responsibilities and expectations, which of course vary by individual and culture. Children love to play and learn, looking forward to becoming preteens. As preteens begin to test their independence, they are eager to become teenagers. Teenagers anticipate the promises and challenges of adulthood. Adults become focused on creating families, building careers, and experiencing the world as an independent person. Finally, many adults look forward to old age as a wonderful time to enjoy life without as much pressure from work and family life. In old age, grandparenthood can provide many of the joys of parenthood without all the hard work that parenthood entails. And as work responsibilities abate, old age may be a time to explore hobbies and activities that there was no time for earlier in life. But for other people, old age is not a phase looked forward to. Some people fear old age and do anything to “avoid” it, seeking medical and cosmetic fixes for the natural effects of age. These differing views on the life course are the result of the cultural values and norms into which people are socialized.
Q. According to the passage, old age is a time for…
C is correct because the keywords in the answer – “hobbies” and “activities” – are mentioned right after the key words – “old age” and “time for”. While option a summarizes part of the text in the passage, it is not preceded by all of the keywords in the question. Options b and d are wrong because the word order has been altered and they no longer match the original statements in the passage.
Although all of us violate norms from time to time, few people would consider themselves deviant. Those who do, however, have often been labeled “deviant” by society and have gradually come to believe it themselves. Labeling theory examines the ascribing of a deviant behavior to another person by members of society. Thus, what is considered deviant is determined not so much by the behaviors themselves or the people who commit them, but by the reactions of others to these behaviors. As a result, what is considered deviant changes over time and can vary significantly across cultures.
Q. According to the paragraph, which of the following best describes the labeling theory?
B is correct because “classification” is another word for “labeling”, and we can find a keyword from the answer in the passage – “reactions”. Some of the other keywords are mentioned throughout the paragraph, but option b summarizes the main concluding statement about the labeling theory. Option a is correct because it is only describing an example of the theory, not the entire theory itself. Option c is wrong because it contradicts the statement made in the passage saying the label is “determined by their own behavior”, and option d is wrong because the theory is not a “categorization of behaviors”.
Meritocracy is another system of social stratification in which personal effort—or merit—determines social standing. High levels of effort will lead to a high social position, and vice versa. The concept of meritocracy is an ideal—that is, a society has never existed where social rank was based purely on merit. Because of the complex structure of societies, processes like socialization, and the realities of economic systems, social standing is influenced by multiple factors, not merit alone. Inheritance and pressure to conform to norms, for instance, disrupt the notion of a pure meritocracy. Sociologists see aspects of meritocracies in modern societies when they study the role of academic performance and job performance, and the systems in place for evaluating and rewarding achievement in these areas.
1. Which of the following best explains meritocracy?
D is correct because we can find the original statement it’s summarizing by looking after the keyword from the question, “meritocracy”, and by finding the keywords, though some are in alternate forms, from the answer – “idealistic”, “social ranking”, and “based on”. Option a is wrong because it is not an “economic system”. Option b and c are wrong because b uses modifiers that are incorrect – “very realistic” – and c alters the word order of other statements, making it untrue.
The earth’s atmosphere exerts a pressure, as does any other gas. Although we do not normally notice atmospheric pressure, we are sensitive to pressure changes—for example, when your ears “pop” during take-off and landing while flying, or when you dive underwater. Gas pressure is caused by the force exerted by gas molecules colliding with the surfaces of objects. Although the force of each collision is very small, any surface of appreciable area experiences a large number of collisions in a short time, which can result in a high pressure. In fact, normal air pressure is strong enough to crush a metal container when not balanced by equal pressure from inside the container.
Atmospheric pressure is caused by the weight of the column of air molecules in the atmosphere above an object, such as the tanker car. At sea level, this pressure is roughly the same as that exerted by a full-grown African elephant standing on a doormat, or a typical bowling ball resting on your thumbnail. These may seem like huge amounts, and they are, but life on earth has evolved under such atmospheric pressure. If you actually perch a bowling ball on your thumbnail, the pressure experienced is twice the usual pressure, and the sensation is unpleasant.
Q. Paragraph 2 states that …
C is correct because we can find a true statement in paragraph 2 that uses the keywords “sea level”, “elephant”, and “doormat”. Option a is wrong because the forces are known; option b is wrong because it is mixing together two different statements; and d is wrong because it uses an incorrect modifier, “small” to change the meaning of the original statement.
One major social determinant of human behavior is our social roles. A social role is an pattern of behavior that is expected of a person in a given setting or group. Each one of us has several social roles. You may be, at the same time, a student, a parent, an aspiring teacher, a son or daughter, a spouse, and a lifeguard. How do these social roles influence your behavior? Social roles are defined by culturally shared knowledge. That is, nearly everyone in a given culture knows what behavior is expected of a person in a given role. For example, what is the social role for a student? If you look around a college classroom you will likely see students engaging in studious behavior, taking notes, listening to the professor, reading the textbook, and sitting quietly at their desks. Of course you may see students deviating from the expected studious behavior such as texting on their phones or using Facebook on their laptops, but in all cases, the students that you observe are attending class—a part of the social role of students.
Social roles, and our related behavior, can vary across different settings. How do you behave when you are engaging in the role of son or daughter and attending a family function? Now imagine how you behave when you are engaged in the role of employee at your workplace. It is very likely that your behavior will be different. Perhaps you are more relaxed and outgoing with your family, making jokes and doing silly things. But at your workplace you might speak more professionally, and although you may be friendly, you are also serious and focused on getting the work completed. These are examples of how our social roles influence and often dictate our behavior to the extent that identity and personality can vary with context (that is, in different social groups).
Q. According to paragraph 2, which of the following is true of social roles?
B is correct because immediately following the keywords from the question, “social roles”, we find some of the keywords from the answer – “different”, “social”, “roles”, as well as synonyms used to sum up the sentence. Option a is incorrect because the very first statement in the paragraph is the opposite. Option c and d are wrong because c uses an incorrect modifier, “certain”, that changes the meaning while d adds modifiers and makes an absolute claim that is not reflected in the passage.
Types of Pressure
Pressure is a force exerted by a substance that is in contact with another substance. Atmospheric pressure is pressure exerted by the mixture of gases (primarily nitrogen and oxygen) in the Earth’s atmosphere. Although you may not perceive it, atmospheric pressure is constantly pressing down on your body. This pressure keeps gases within your body, such as the gaseous nitrogen in body fluids, dissolved. If you were suddenly ejected from a spaceship above Earth’s atmosphere, you would go from a situation of normal pressure to one of very low pressure. The pressure of the nitrogen gas in your blood would be much higher than the pressure of nitrogen in the space surrounding your body. As a result, the nitrogen gas in your blood would expand, forming bubbles that could block blood vessels and even cause cells to break apart.
Atmospheric pressure does more than just keep blood gases dissolved. Your ability to breathe—that is, to take in oxygen and release carbon dioxide—also depends upon a precise atmospheric pressure. Altitude sickness occurs in part because the atmosphere at high altitudes exerts less pressure, reducing the exchange of these gases, and causing shortness of breath, confusion, headache, lethargy, and nausea. Mountain climbers carry oxygen to reduce the effects of both low oxygen levels and low barometric pressure at higher altitudes.
Q. According to paragraph 2, which of the following is NOT true about atmospheric pressure?
C is correct because the modifier “sole” has been added and is not included in the original statement about altitude sickness in paragraph 2. In fact, the sentence states that the lower pressure is only part of the cause of altitude sickness.