Exam 4: HESI-A2-Reading

Placebos A placebo is any kind of drug, procedure, or treatment that does not have legitimate medicinal properties. Placebos do not contain any sort of active ingredient meant to treat an illness or injury. Placebo pills, for example, might be made out of sugar or corn starch. However, even though placebos contain no medicine whatsoever, people who take them often experience reactions that cannot possibly be triggered by the substances in the pills themselves. This is known as the placebo effect. In one study of the placebo effect, volunteers were given a starch pill and told that it was a stimulant similar to caffeine. These volunteers reported feeling more alert and slightly jittery. They also showed an increased heart rate and a spike in blood pressure. Researchers then gave the exact same placebo pill to a different group of people, this time telling them that it was a depressant. The second group of participants reported feeling drowsy and sluggish, and showed a reduced heart rate and lowered blood pressure. Researchers use placebos to evaluate the effectiveness and possible side effects of new drugs. For example, during a study for a drug to treat depression, half of the participants might be given the actual drug while the other half are given a placebo. None of the participants know whether or not they are taking the real drug or the placebo. Researchers can then compare the results between the two groups to determine whether or not the drug produces the desired results and examine the side effects. Question: What is the best definition for the word 'jittery' in paragraph 2?

Concussions Concussions are brain injuries that occur when a person receives a blow to the head, face, or neck. Although most people who suffer a concussion experience initial bouts of dizziness, nausea, and drowsiness, these symptoms often disappear after a few days. The long-term effects of concussions, however, are less understood and far more severe. Recent studies suggest that people who suffer multiple concussions are at significant risk for developing chronic traumatic encephalopathy (CTE), a degenerative brain disorder that causes a variety of dangerous mental and emotional problems to arise weeks, months, or even years after the initial injury. These psychological problems can include depression, anxiety, memory loss, inability to concentrate, and aggression. In extreme cases, people suffering from CTE have even committed suicide or homicide. The majority of people who develop these issues are athletes who participate in popular high-impact sports, especially football. Improvements in diagnostic technology have provided substantial evidence to link severe-and often fatal-psychological disorders to the head injuries players receive while on the field. Recent autopsies performed on the brains of football players who have committed suicide have shown advanced cases of CTE in every single victim. In response to the growing understanding of this danger, the National Football League (NFL) has revised its safety regulations. There is hope that these new regulations, coupled with advances in helmet design, will reduce the number of concussions player endure, and thus curb the number of CTE cases. Efforts by the NFL and other professional sports leagues are certainly laudable. However, new regulations at the professional level cannot protect amateur players, especially young people. Fatal cases of CTE have been reported in victims as young as 21. With appropriate equipment and form, tackling need not be dangerous. Proper tackling form-using the arms and shoulders to aim for a player's midsection rather than leading with the top of the head-should be taught at an early age. Youth, high school, and college leagues should also adopt safety rules even more stringent than the NFL's. Question: What is the meaning of the word 'degenerative' used in the second paragraph to describe 'a degenerative brain disorder'?

Placebos A placebo is any kind of drug, procedure, or treatment that does not have legitimate medicinal properties. Placebos do not contain any sort of active ingredient meant to treat an illness or injury. Placebo pills, for example, might be made out of sugar or corn starch. However, even though placebos contain no medicine whatsoever, people who take them often experience reactions that cannot possibly be triggered by the substances in the pills themselves. This is known as the placebo effect. In one study of the placebo effect, volunteers were given a starch pill and told that it was a stimulant similar to caffeine. These volunteers reported feeling more alert and slightly jittery. They also showed an increased heart rate and a spike in blood pressure. Researchers then gave the exact same placebo pill to a different group of people, this time telling them that it was a depressant. The second group of participants reported feeling drowsy and sluggish, and showed a reduced heart rate and lowered blood pressure. Researchers use placebos to evaluate the effectiveness and possible side effects of new drugs. For example, during a study for a drug to treat depression, half of the participants might be given the actual drug while the other half are given a placebo. None of the participants know whether or not they are taking the real drug or the placebo. Researchers can then compare the results between the two groups to determine whether or not the drug produces the desired results and examine the side effects. Question: Based on the passage, what can be inferred regarding the volunteers mentioned in paragraph 2?

Hangovers Veisalgia, more commonly known as a hangover, is the name for the range of unpleasant physical effects that occur following the excessive consumption of alcoholic beverages. The most commonly experienced effects include nausea, vomiting, sensitivity to light and sound, headache, thirst, and lethargy. The degree of the hangover's severity is determined by factors occurring both before and after the alcohol is metabolized. The main pre-metabolic cause of veisalgia is the quantity of alcohol consumed. Binge drinking is one of the most notorious contributors to hangovers. Empirical research suggests that even an increase in consumption from four to six beers can result in twice the susceptibility to end up with a hangover. Another pre-consumption factor that contributes to hangovers is the amount of congeners present in the alcohol. Congeners are chemical substances produced during the fermentation process that give the alcohol color, taste, and aroma. Recent studies have shown that alcohol with a high congener content, such as bourbon (which is brown), is three times as likely to cause a hangover as the same amount of a low-congener alcohol, such as vodka (which is clear). Post-metabolic causes of veisalgia have less to do with the amount or kind of alcohol consumed and more to do with genetics. One of the major post-metabolic causes of veisalgia is the production of acetaldehyde. During the initial stages of metabolization, the liver produces an enzyme known as alcohol dehydrogenase. This enzyme works to convert the ethanol present in alcohol into the compound acetaldehyde. Studies have shown that individuals who lack this enzyme-and thus also lack the ability to break down ethanol in the liver-have a much higher rate of hangover occurrence, and experience more immediate and more severe hangover symptoms. Question: What is the best summary of this passage?

Glowing in the Dark Have you ever wondered how glow-in-the-dark things actually glow in the dark? Most glow-in-the-dark items glow because of something called phosphorescence or photoluminescence. Phosphorescent items must be "charged" under a bright light before they actually glow in the dark. This charging process works because of a substance called phosphor. When light from the sun or a lamp hits phosphor, the phosphor molecules absorb the light and become energized. As the phosphor molecules release the stored energy, they emit a dim light that is visible in the dark. The color of the light that they produce depends on the color of the dye added to the glow-in-the-dark item. Usually, green dye is added to the phosphors to make the light easier to see. Although any color can be used, the human eye sees green light most clearly in the dark. There are also a few glow-in-the-dark items that do not need to be charged. Emergency exit signs, gun sights, and certain kinds of expensive wristwatches glow because of radioluminescence. In these items, the phosphor is mixed with a radioactive element called tritium. The radiation from the tritium provides energy to the phosphor. It is almost as if there are thousands of tiny lamps constantly shining on the phosphor. Because their phosphor is always energized, these radioluminescent items are always glowing. One other kind of glow-in-the-dark item that does not require charging is the glow stick. Glow sticks do not need to be held under light and do not contain any radioactive elements. Instead, glow sticks glow using chemiluminescence. Glow sticks contain a fluorescent dye and a thin glass tube that contains a chemical. To activate a glow stick, you bend the plastic container, causing the glass to break. The chemical inside the glass then mixes with the dye. The combination of the chemical and the dye produces visible light. Question: Which of the following can be inferred from the passage?

Basketball Ankle Injury Treatments Basketball players are more likely than any other sports players to injure their ankles. The most common ankle injuries among basketball players are inversion (turning inward) and eversion (turning outward) of the ankle. The sharp twists, frequent running, constant jumping, and sudden stopping associated with basketball put tremendous pressure on a player's ankle joint. The two main ways that players and trainers try to treat and prevent these injuries are taping and bracing. Taping simply involves wrapping special tape snugly around the ankle joint. Although it is simple to apply, there are some drawbacks. Taping is not very expensive when used once, but when used throughout the season, taping is three times more costly than bracing. Taping also loosens with physical activity; after only ten minutes of exercise, the tape will become 50% looser. After one hour of exercise, taping offers no significant support whatsoever. Bracing has proven to be more effective than taping in a number of different studies. It is also much more cost effective throughout a season. Several types of ankle braces are available for use, ranging from cloth lace-on braces to more rigid plastic braces. Braces decrease the range of motion of the ankle more than taping does, and, therefore, help to prevent future ankle injuries. However, despite the benefits of ankle braces over ankle tape, many players find that braces restrict movement capabilities and also cause discomfort. What is the best meaning of the word "snugly," as used in paragraph 2?

The Liver The liver is one of the largest and most vital organs in the body. It is located on the right side of the body and is protected by the rib cage. The liver performs many important jobs, including breaking down nutrients, removing toxins, and destroying damaged blood cells. The liver's main function is to filter blood. Blood travels to the liver from the digestive tract. The liver processes this blood, removing toxins and metabolizing nutrients. The liver also secretes bile during this process. Bile is stored in the gallbladder and released into the large intestine. Bile aids in the digestion of fats. The liver also makes proteins necessary for blood clotting, removes worn-out blood cells, helps to regulate blood sugar levels, and stores vitamins A, D, E, K, and B12. There are several diseases that can affect the liver. Because the liver performs so many important functions in the body, liver problems can be life-threatening. Hepatitis is a disease characterized by inflammation of the liver. Left untreated, certain types of hepatitis can be fatal. Cirrhosis is another dangerous liver condition. Cirrhosis develops when healthy liver tissue is replaced by scar tissue. This is most often caused by long-term alcohol abuse. Cirrhosis can cause swelling, internal bleeding, and eventually, liver failure. The only cure for cirrhosis is a full liver transplant. Which detail is not included in the passage?

Your Bones At birth, the human body contains over 270 bones. However, as the body grows, some of these bones fuse together. The average adult body contains 206 bones. Together, these bones form the skeleton. The skeleton has many vital functions, including protecting internal organs, providing support, enabling movement, generating blood cells, storing calcium, and helping to regulate the endocrine system. Although we only have one skeleton, it is divided into two major regions: the axial and the appendicular skeletons. The former refers to everything on the body's middle axis, such as the skull, sternum, and vertebrae, while the latter refers to the bones that make up the arms, legs, pelvis, and shoulder girdle. These bones include the femur, the tibia, the ulna, and the radius. Bones are further classified according to their shape and function. The five classifications of bones are: long, short, flat, irregular, and sesamoid bones. Long bones include the fibula and tibia. The carpal bones in the wrist are examples of short bones. Flat bones are thin and curved and include the ribs, the sternum, and some skull bones. Irregular bones, such as the vertebrae and some facial bones, have complex shapes. Finally, sesamoid bones are small, round bones that form in tendons. There are sesamoid bones in the hands, wrists, and feet, but the most familiar sesamoid bone is the patella, or kneecap. Question: According to the text, which body part is described as having bones belonging to two of the five classifications?

Autism and Vaccines Autism spectrum disorders (ASD) are a range of psychological conditions characterized by challenges with social interaction, behavior, speech, and nonverbal communication. While there is no general consensus among medical professionals about the underlying causes of ASD, theories range from genetic inheritance to environmental factors. One of the most controversial theories to have emerged in recent times is that ASD could be caused by the MMR [mumps, measles, rubella] vaccine that was first developed in the 1960s. The vaccine is a mixture of three live viruses and is administered via injection to children when they are one year old. By the late 1990s, this vaccination had led to the near-eradication of measles in countries that employed widespread inoculation. However, a combination of spurious scientific data and alarmist media attention led to an entirely preventable resurgence in measles cases in the early 21^st century. The first claims of a connection between the MMR vaccine and autism were made in 1998, when an article in The Lancet, a respected British medical journal, reported on eight cases of autism that could possibly be traced back to the administration of an MMR vaccine. An onslaught of media coverage followed the publication of this article. The popular press quickly seized upon this story; in 2002, over 1200 articles were written about the link between MMR vaccines and ASD. Less than 30% of these articles, however, mentioned that an overwhelming amount of scientific evidence suggested that these vaccinations were completely safe. Question: What is the main idea of the passage?

Diabetes There are two types of diabetes: Type 1 and Type 2. Both types of diabetes can cause a variety of serious health risks if left untreated. Some of these health problems include kidney disease, blindness, heart disease, and strokes. About 5-10% of people with diabetes have Type 1 diabetes. Type 1 diabetes most commonly develops in young people. In Type 1 diabetes, the immune system destroys the cells in the pancreas that secrete insulin. Without insulin, the body's cells cannot absorb glucose, and thus cannot produce energy. Symptoms appear after about 90% of the cells have been destroyed. Although most cases of Type 1 diabetes are genetic, some have arisen in people who have had viral infections of the pancreas. Most people who have diabetes (90-95%) have type 2 diabetes, which most commonly develops in people over age 40. Type 2 diabetes results from the inability of tissues to respond to insulin-a condition called insulin resistance. As Type 2 diabetes progresses, the pancreas produces less and less insulin, resulting in a condition called insulin deficiency. There is no cure for either Type 1 or Type 2 diabetes. However, there are ways to manage both types. For Type 1 diabetes, treatment requires receiving regular insulin injections. Type 2 diabetes can also be treated with insulin injections, but can be also be managed with lifestyle changes, such as weight loss, exercise, and reducing intake of carbohydrates. What is the best summary for the passage?

Hangovers Veisalgia, more commonly known as a hangover, is the name for the range of unpleasant physical effects that occur following the excessive consumption of alcoholic beverages. The most commonly experienced effects include nausea, vomiting, sensitivity to light and sound, headache, thirst, and lethargy. The degree of the hangover's severity is determined by factors occurring both before and after the alcohol is metabolized. The main pre-metabolic cause of veisalgia is the quantity of alcohol consumed. Binge drinking is one of the most notorious contributors to hangovers. Empirical research suggests that even an increase in consumption from four to six beers can result in twice the susceptibility to end up with a hangover. Another pre-consumption factor that contributes to hangovers is the number of congeners present in the alcohol. Congeners are chemical substances produced during the fermentation process that give the alcohol color, taste, and aroma. Recent studies have shown that alcohol with a high congener content, such as bourbon (which is brown), is three times as likely to cause a hangover as the same amount of a low-congener alcohol, such as vodka (which is clear). Post-metabolic causes of veisalgia have less to do with the amount or kind of alcohol consumed and more to do with genetics. One of the major post-metabolic causes of veisalgia is the production of acetaldehyde. During the initial stages of metabolization, the liver produces an enzyme known as alcohol dehydrogenase. This enzyme works to convert the ethanol present in alcohol into the compound acetaldehyde. Studies have shown that individuals who lack this enzyme-and thus also lack the ability to break down ethanol in the liver-have a much higher rate of hangover occurrence, and experience more immediate and more severe hangover symptoms. Question: Which of the following is NOT a cause of veisalgia?

Fibromyalgia Fibromyalgia is a chronic condition that affects an estimated 3-6% of the world's population. The disorder is characterized by both physiological and psychological symptoms, including nerve pain, fatigue, sleep and mood disturbances, headaches, bowel problems, and incontinence. The exact cause of fibromyalgia is unknown. For some people, fibromyalgia symptoms begin after some sort of physical or psychological stress. However, for others, the onset of symptoms is gradual. Research has shown that genetics may play a part, but there is also evidence that environmental factors can contribute. The wide variety of symptoms made it difficult to diagnose and treat for many years, though recent research has made some promising advances. Although a cure for fibromyalgia has not yet been developed, research has shown that some of the symptoms can be treated with pharmaceuticals, such as tricyclics or gabapentinoids, or non-pharmacological methods, such as meditation, mindfulness, and cognitive behavior therapy. The most successful pharmacological treatment for fibromyalgia has been tricyclic antidepressants, such as amitriptyline and nortriptyline. These drugs increase the levels of the neurotransmitters serotonin and norepinephrine, which are often found at decreased levels in the brains of people who suffer from chronic pain. By boosting endorphins and relaxing muscles, tricyclics can ease some of the musculoskeletal pain felt by people with fibromyalgia. Question: Which of the following is NOT true according to the passage?

Sports Drinks When you sweat heavily, your body loses electrolytes and water. The most important electrolytes are potassium and sodium-these substances keep your body's cells working properly. Commercials for sports drinks claim that their products will replenish the electrolytes lost during exercise. However, sports drinks are not really necessary for most people. Eating a normal diet that contains healthy amounts of sodium and potassium will maintain the electrolyte balance in your body. Unless you are exercising very intensely for more than 60 minutes, you do not need to use a sports drink to replace lost electrolytes. Most people believe that sports drinks are healthy beverages-after all, if athletes drink them, they must be good for you. On the contrary, sports drinks are filled with artificial ingredients and sugar. One 20-ounce bottle of an average sports drink contains 34 grams of sugar and 130 calories. These empty calories can actually cause you to gain weight instead of helping to keep you fit. One study presented at the 2012 Obesity Society's annual scientific meeting revealed that teenagers gained an average of 3.5 pounds every two years just by consuming a bottle of sports drink every day. The best beverage for you to drink before, during, or after a workout is water. Water has no sugar, no salt, no calories, and no artificial flavors or colors. Water will rehydrate your body and quench your thirst better than any other drink. Unless you are a serious athlete who regularly exercises for more than 60 minutes at a time, sports drinks ultimately do more harm than good. Question: What is the author's general opinion regarding sports drinks?

The Science of Taste Have you ever looked at your tongue in a mirror? If so, you have probably noticed that it is bumpy. The bumps on your tongue are called papillae. Each one of the papillae contains hundreds of taste buds. You also have taste buds on the roof of your mouth and on your epiglottis, which is located at the top of your throat. The taste buds send messages to your brain that tell you about its basic flavor-that is, whether you are eating something salty, sweet, bitter, sour, or umami. Umami is hard to describe, but it is most often called a "meaty" or "savory" flavor. Foods with an umami flavor include meat broth, cheese, and soy sauce. Your mouth and tongue also have receptors that send information about things besides the basic flavors of food. Your mouth has temperature receptor cells that can tell whether a food is piping hot or ice cold. Other receptors give information about the texture of food or how spicy it is. But just being able to tell whether what you are eating is sour, cold, crunchy, or spicy is not truly tasting the food. For example, orange soda and root beer are both sweet, cold, and bubbly, but they do not taste the same. In order to get the full flavor of your food, you also need to use your sense of smell. The upper part of your nose contains special cells called olfactory receptors. They send messages about what things smell like to your brain. As you chew your food, chemicals quickly travel to the olfactory receptors in your nose. When your brain gets information from both the olfactory receptors and the taste buds, you experience the full flavor of what you are eating. Question: Which detail is NOT included in the passage?

Brain Freeze "Brain Freeze" headaches-known to scientists as sphenopalatine ganglioneuralgia -are most often triggered when cold food or drink comes into contact with the roof of your mouth. In order to discover more about this phenomenon, researchers at Harvard Medical School hooked volunteers up to trans-cranial Dopplers, machines that allow scientists to study blood flow in the brain. The volunteers were then given cups of ice water and instructed to drink it using a straw held right up against the roof of the mouth. The volunteer gave a signal when he or she felt a "brain freeze" headache begin and another signal when it ended. This experiment allowed the scientists to observe changes in brain blood flow before, during, and after a "brain freeze" headache. The scientists found that when the subjects were experiencing a "brain freeze", the anterior cerebral artery (a major blood vessel in the brain) dilated rapidly. Because the artery becomes wider, more blood flows into the brain. This creates an increase in pressure inside the skull, which is what causes the pain. As soon as the artery shrinks to its normal size, the "brain freeze" headache disappears. This may explain why "brain freeze" headaches hurt, but it does not tell us why they happen in the first place. Scientists do not yet have any definite answers to this question, but they do have some ideas. One theory suggested by the researchers at Harvard Medical School is that a brain freeze is a way of protecting the brain from cold. When the anterior cerebral artery dilates, it allows a flood of warm blood inside the brain, thus keeping it warm. According to the passage, what was the result of the experiment?

Concussions Concussions are brain injuries that occur when a person receives a blow to the head, face, or neck. Although most people who suffer a concussion experience initial bouts of dizziness, nausea, and drowsiness, these symptoms often disappear after a few days. The long-term effects of concussions, however, are less understood and far more severe. Recent studies suggest that people who suffer multiple concussions are at significant risk for developing chronic traumatic encephalopathy (CTE), a degenerative brain disorder that causes a variety of dangerous mental and emotional problems to arise weeks, months, or even years after the initial injury. These psychological problems can include depression, anxiety, memory loss, inability to concentrate, and aggression. In extreme cases, people suffering from CTE have even committed suicide or homicide. The majority of people who develop these issues are athletes who participate in popular high-impact sports, especially football. Improvements in diagnostic technology have provided substantial evidence to link severe-and often fatal-psychological disorders to the head injuries players receive while on the field. Recent autopsies performed on the brains of football players who have committed suicide have shown advanced cases of CTE in every single victim. In response to the growing understanding of this danger, the National Football League (NFL) has revised its safety regulations. There is hope that these new regulations, coupled with advances in helmet design, will reduce the number of concussions player endure, and thus curb the number of CTE cases. Efforts by the NFL and other professional sports leagues are certainly laudable. However, new regulations at the professional level cannot protect amateur players, especially young people. Fatal cases of CTE have been reported in victims as young as 21. With appropriate equipment and form, tackling need not be dangerous. Proper tackling form-using the arms and shoulders to aim for a player's midsection rather than leading with the top of the head-should be taught at an early age. Youth, high school, and college leagues should also adopt safety rules even more stringent than the NFL's. Question: Which would best replace 'stringent,' used in the last sentence of the passage?

PTSD in Female Veterans Post-traumatic stress disorder (PTSD) is a severe anxiety disorder that affects millions of people around the world. Individuals can develop PTSD after experiencing any event that results in psychological trauma. Symptoms of PTSD involve flashbacks to the traumatic event, nightmares, obsessive behavior, anger, insomnia, difficulty concentrating, and hypervigilance. Individuals who suffer from PTSD can experience significant difficulties in social relationships, have lower self-esteem, and have trouble maintaining employment. People with PTSD experience a higher risk of committing suicide and developing a substance abuse disorder. Although PTSD can affect any individual, military veterans are especially susceptible. Furthermore, within this population, women are more than twice as likely as men to develop PTSD. Although studies investigating precisely why women are more likely than men to experience PTSD have not yet been completed, some experts have theorized that low unit cohesion is a major factor. Unit cohesion, defined as the mutual bonds of friendship and support among members of a military unit, is thought to be helpful in reducing the incidence of developing PTSD. Women are more likely than men to experience low unit cohesion for a variety of reasons. One of the most obvious factors is the relative lack of females in the military; currently, women make up only 20% of the armed forces. Pervasive male prejudice against women is another factor that can diminish unit cohesion for female soldiers. Perhaps the biggest impediment to achieving quality treatment for women suffering from wartime PTSD is a shortage of research. While both the VA and independent agencies have completed hundreds of studies researching the prevention of and treatment for PTSD amongst general military populations, there have been no studies completed that solely target women. More must be done to help women who have sacrificed so much for their country. Question: What is the main idea of the passage?

Mercury in Fish Mercury is a highly toxic metal found in neon signs, fluorescent lights, older thermometers, and certain kinds of telescopes. It can also be found in something that many people eat on a regular basis: fish. The mercury we might find in a can of tuna is most likely an indirect result of the coal industry. Mercury, which is naturally found in coal, is released into the air when coal is burned. It finds its way into waterways via mercury-laced rain. Mercury accumulates in certain kinds of fish through a process called biomagnification. Biomagnification occurs when a substance enters the food chain in small amounts at the very bottom and then increases in concentration in animals higher up on the food chain. Once a fish eats another creature containing mercury, the mercury does not leave that fish's body but instead is stored in fat. Therefore, the mercury continually accumulates as more mercury-contaminated fish are eaten. Despite the toxicity of mercury and the widespread nature of fish contamination, there is no need for the public to be overly apprehensive. Many popular fish, such as salmon, catfish, or tilapia, are generally safe to eat. Other fish, especially tuna and grouper, should only be eaten in moderation. Young children and pregnant women should be especially cautious about how many servings of mercury-contaminated fish they have per week. It is recommended that people in these groups not eat more than 2 servings of mercury-contaminated fish per week. Fish with the highest levels of mercury include shark, swordfish, and king mackerel. All people should avoid eating large amounts of these kinds of fish, and no one should eat these fish more frequently than once a month. What is the purpose of the passage?

The Pilomotor Reflex Have you ever experienced the pilomotor reflex? Chances are that you have. The pilomotor reflex is actually something most people experience every day: goose bumps. Goose bumps (also called goose flesh and goose pimples) are small bumps on the skin. They are created when tiny muscles beneath the hairs on your skin contract, pulling the hair into an upright position. They can occur anywhere that you have hair on your body, but they are most common on your arms and legs. Goose bumps are an involuntary reaction to many different sensations, such as cold, fear, or even happiness. Humans are not the only animals that get goose bumps. When cats or dogs are threatened by an enemy, the pilomotor reflex will cause their fur to stand on end. This makes the animal look larger, which might scare away the enemy. Porcupines also experience the pilomotor reflex; a frightened porcupine will raise its quills when it is in danger. This not only makes the porcupine look bigger, it frightens enemies away by drawing attention to the sharp quills. The pilomotor reflex can also help animals stay warm by trapping body heat closer to their skin. Because human beings have much less body hair than most other animals, goose bumps do not make us seem larger or more intimidating. They also do not help to keep us very warm, although they do help to prevent some heat from leaving the body. For the most part, the pilomotor reflex is much more important for animals than it is for people. In fact, many scientists think that the pilomotor reflex is actually completely useless for humans. Question: Which of the following is NOT true of the pilomotor reflex in non-human animals?

Balance Everyone knows that your ears are responsible for your sense of hearing. But did you also know that your ears are also partially responsible for your sense of balance? Your inner ear contains something called the vestibular system, which is a key component in your body's ability to establish and maintain balance. The vestibular system mainly consists of three semicircular canals. Each semicircular canal has a different orientation, allowing them to detect a variety of movements. The canals are filled with a fluid called endolymph. When you move your head, the fluid in the canals also moves; this movement sends signals to the brain about the position of your head. Your brain uses this information to help your body stay balanced. Damage to the vestibular system caused by disease or injury can severely affect a person's balance. Consuming too much alcohol can also temporarily affect the vestibular system. Because alcohol thins the blood, it also changes the viscosity of the endolymph. The thinned-out endolymph sends signals to your brain that your body is rotating even though it is not. This is why many people feel like the room is spinning when they are drunk. What is the best summary for the passage?