Practice Test - 34 | Reading Practice Tests for IELTS Academic PDF Download

A. To understand more about the earth's history, humans have often looked to the natural environment for insight into the past. The bristlecone pine (Pinus longaeva), of the White Mountains in California, has served this purpose greater than any other species of free on the planet. Conditions here are brutal: scant precipitation and low average temperatures mean a short growing season, only intensified by ferocious wind and mal-nutritious rocky. Nevertheless, bristlecone pines have claimed these barren slopes as their permanent home. Evolving here in this harsh environment, super-adapted and without much competition, bristlecones have earned their seat on the longevity throne by becoming the oldest living trees on the planet. Results of extensive studies on bristlecone pine stands have shown that in fact such, environmental limitations are positively associated with the attainment of great age. This intriguing phenomenon will be discussed further on. 

B. But exactly how old is old? Sprouted before the invention of Egyptian hieroglyphs and long before the teachings of Jesus of Nazareth, Dethuselah is the oldest bristlecone alive at roughly 4,700 years. Although specimens of this age do not represent the species' average, there are 200 trees more than 3,000 years old, and two dozen more than 4,000. Considering that these high ages are obtained in the face of such remarkable envnonmental adversity, the bristlecone pines have become the focus of much scientific examination over the past half century. 

C. Perhaps most interested in the bristlecone pine are dendochronologists, or tree-ring daters. With every strenuous year that passes in the White Mountains, each bristlecone grows and forms a new outer layer of cambium that reflects a season's particular ease or hardship. So while, growing seasons may expand or shrink, the trees carry on, their growth rings faithfully recording the bad years alongside the goods. Through examining the annual growth rings of both living and dead specimens, taking thousands of core samples, and by processes of cross-dating between trees and other qualitative records, scientists have compiled a continuous tree-ling record that dates back to the last Ice Age between eight and ten thousand years ago. Among other linked accomplishments, this record has enhanced the dating process, helping to double-cheek and correct the radiocarbon-14 method to more accurately estimate the age of organic material. 

D. Now more than ever the importance of monitoring the bristiecone is being realized. As our global climate continues to undergo its most recent and abrupt atmospheric change, these ancient scribes continue to respond. Since, the rings of wood formed each year reveal the trees' response to climatic conditions during a particular growing seasons, in their persistence they have left US natural recordings of the past, markers of the present, and clues to the future. 

E. The species' name originates from the appearance of its unusual cones and needles. The bristlecone's short, pale needles are also trademarks, bunching together to form foxtail-like bundles. As is the case of moat conifer needles, these specialized leaves cluster together to shelter the stomata so very little moisture is lost through them. This adaptation helps the bristlecone photosynthesize during particularly brutal months, Saving the energy of constant needle replacement and providing a stable supply of chlorophyll. For a plant trying to store so much energy, bristlecone seeds are relatively large in size. They are first reproduced when trees reach ages between thirty and seventy-five years old Germination rates are generally high, in part because seeds require little to no initial stratification. Perhaps the most intriguing physical characteristic of a mature bristlecone, however, is its ratio of living to dead wood on harsh sites and how this relates to old age. In older trees, however, especially in individuals over 1,500 years, a strip-bark trait is adaptive. This condition occurs as a result of cambium dieback, which erodes and thereby exposes certain areas of the bole, leaving only narrow bands of bark intact 

F. The technique of cambial edge retreat has help promote old age in bristlecone pine, but that certainly is not the only reason. Most crucial to these trees' longevity is their compact size and slow rates of growth. By remaining in most cases under ten meters tall, bristlecones stay close to the limited water supply and can hence support more branches and photosynthesizing. Combined with the dry, windy, and often freezing mountain a ữ , slow growth guarantees the hrifltlecones tight, fibrous rings with a high resin content and structural strength. The absence of natural disaster has also safeguarded the bristlecone's lengthy lifespan. Due to a lack of ground cover vegetation and an evenly spaced layout, bristlecone stands on the White Mountain peaks have been practically unaffected by fire. This lack of vegetation also means a lack of competition for the bristlecones. 

G. Bristlecone pine's restricted to numerous, rather isolated stands at higher altitudes in the southwestern United States. Stands occur from the Rocky Mountains, through the Colorado Plateau, to the western margin of the Great Basin. Within this natural range, the oldest and most widely researched stands of bristlecones occur in California's White Mountains. Even just 200 miles away from the Pacific Ocean, the White Mountains are home to one of this country's few high-elevation deserts. Located in the extreme eastern rain shadow of the Sierra Nevada, this region receives only 12.54 inches of precipitation per year and experiences temperatures between -20F and +50F. The peaks south of the Owens Valley, are higher up than they might appear from a distance. Although most summits exist somewhere around 11,000 feet, snow-capped White Mountain Peak, for which the range is named, stands at 14,246 feet above sea level. That said, to reach areas of pure bristlecone is an intense journey all to itself. 

H. With seemingly endless areas of wonder and interest, the bristlecone pines have become subject to much research over the past half-century. Since the annual growth of these ancient organisms directly reflects the climatic conditions of a particular time period, bristlecones are of greatest significance to dendochronologists, or tree-ring specialists. Dating any tree is simple and can be done within reasonable accuracy just by counting out the rings made each year by the plant's natural means of growth. By carefully compiling a nearly 10,000- year-old bristlecone pine record, these patient scientists have accurately corrected the carbon-14 dating method and estimated ages of past periods of global climate change. What makes this record so special to dendochronologists, too, is that, nowhere, throughout time, is precisely the same long-term sequence of wide and narrow rings repeated, because year-to-year variations in climate are never exactly the same. 

I. Historically the bristlecone's remote location and gnarled wood have deterred commercial extraction, but nothing on earth will go unaffected by global warming. If temperatures rise by only 6 degrees F, which many experts say is likely this century, about two-thirds of the bristlecones' ideal habitat in the White Mountains effectively will be gone. Almost 30,000 acres of National Forest now preserves the ancient bristlecone, but paved roads, campsites, and self-guided trails have led only to more human impact. In 1966, the U.S.F.S reported over 20,000 visitors to the Ancient Bristlecone Pine Forest, a figure which could exceed 40,000 today. Over the past hundreds of thousands of years, this species has endured in one of earth's most trying environments; they deserve our respect and reverence. As global climate change slowly alters their environment, we as humans must do our part to raise awareness and lower our impact.
Questions 1-4: The reading Passage has nine paragraphs A-I. Which paragraph contains the following information? Write the correct letter A-I, in boxes 1-4 on your answer sheet.
Q.1. Human activity threats bristlecone pines habitat
Q.2. Explanations for a ring of bristlecone pines
Q.3. An accountable recording provided from the past till now
Q.4. Survived in a hostile environment

Questions 5–7: Choose the correct letter, A, B, c, or D.Write your answers in boxes 5-7 on your answer sheet.
Q.5. According to passage A, what aspect of bristlecone pines attracts the author’s attention?
A. Brutal environment they live
B. Remarkable long age
C. They only live in California
D. Outstanding height
Q.6. Why do we investigate Bristlecone pines in higher altitudes of California’s the White Mountains?
A. Because the oldest ones researched in this region
B. Because most bizarre ones are in this region
C. Because precipitation is rich in this region
D. Because sea level is comparatively high in this region
Q.7. Why there are repeated patterns of wide and narrow rings?
A. Because sea level rises which affect tree ring
B. Because the tree ring pattern is completely random
C. Because ancient organisms affect its growth
D. Because the variation of climate change is different

Questions 8-13: Complete the following summary of the paragraphs of Reading Passage, using no more than three words from the Reading Passage for each answer. Write your answers in boxes 8-13 on your answer sheet.

The bristlecone’s special adaptation is beneficial for photosynthesizing, reserving the____8_____of leave replacement, and providing sufficient chlorophyll. Probably because seeds do not rely on primary _____9_____, the Germination rate is high. Because of cambium dieback, only narrow ____10_____ remain complete. Due to multiple factors such as windy, cold climate and____11_____, bristlecones’ rings have tight and solid structure full of resin. Moreover, bristlecone stands are safe from fire because of little ____12_____plants spread in this place. The summits of Owens Valley are higher than they emerge if you observe from a ___13_____.

You should spend about 20 minutes on Questions 14-27, which are based on Reading Passage 2 on the following pages.

A. Ken Glander, a primatologist from Duke University, gazes into the canopy, tracking the female's movements. Holding a dart gun, he waits with infinite patience for the right moment to shoot. With great care, Glander aims and fires. Hit in the rump, the monkey wobbles. This howler belongs to a population that has lived for decades at Hacienda La Pacifica, a working cattle ranch in Guanacaste province. Other native primates — white-faced capuchin monkeys and spider monkeys — once were common in this area, too, but vanished after the Pan-American Highway was built nearby in the 1950s. Most of the smrounding land was clear-cut for pasture.
Monkeys and Forests B. Howlers persist at La Pacifica, Glander explains, because they are leaf-eaters. They eat fruit, when it’s available but, unlike capuchin and spider monkeys, do not depend on large areas of fruiting trees. “Howlers can survive anyplace you have half a dozen trees, because theft eating habits are so flexible,” he says. In forests, life is an arms race between trees and the myriad creatures that feed on leaves. Plants have evolved a variety of chemical defenses, ranging from bad-tasting tannins, which bind with plantproduced nutrients, rendering them indigestible, to deadly poisons, such as alkaloids and cyanide.
Monkeys and Forests C. All primates, including humans, have some ability to handle plant toxins. “We can detoxify a dangerous poison known as caffeine, which is deadly to a lot of animals” Glander says. For leaf-eaters, long term exposure to a specific plant toxin can increase their ability to defuse the poison and absorb the leaf nutrients. The leaves that grow in regenerating forests, like those at La Pacifica, are actually more howler friendly than those produced by the undisturbed, centuries-old trees that survive farther south, in the Amazon Basin. In younger forests, frees put most of their limited energy into growing wood, leaves and fruit, so they produce much lower levels of toxin than do wellestablished, old-growth trees. 

D. The value of maturing forests to primates is a subject of study at Santa Rosa National Park, about 35 miles northwest of Hacienda La Pacifica. The park hosts populations not only of mantled howlers but also of white-faced capuchins and spider monkeys. Yet the forests there are young, most of them less than 50 years old. Capuchins were the first to begin using the reborn forests, when the trees were as young as 14 years. Howlers, larger and heavier than capuchins, need somewhat older trees, with limbs that can support their greater body weight. A working ranch at Hacienda La Pacifica also explain their population boom in Santa Rosa. “Howlers are more resilient than capuchins and spider monkeys for several reasons,” Fedigan explains. “They can live within a small home range, as long as the trees have the right food for them, spider monkeys, on the other hand, occupy a huge home range, so they can’t make it in fragmented habitat.” 

E. Howlers also reproduce faster than do other monkey species in the area. Capuchins don’t bear their first young until about 7 years old, and spider monkeys do so even later, but howlers give birth for the first time at about 3.5 years of age. Also, while a female spider monkey will have a baby about once every four years, well-fed howlers can produce an infant every two years. 

F. The leaves howlers eat hold plenty of water, so the monkeys can survive away from open streams and water holes. This ability gives them a real advantage over capuchin and spider monkeys, which have suffered during the long, ongoing drought in Guanacaste. 

G. Growing human population pressures in Central and South America have led to persistent destruction of forests. During the 1990s, about 1.1 million acres of Central American forest were felled yearly. Alejandro Estrada, an ecologist at Estacion de Biologia Los Tuxtlas in Veracruz, Mexico, has been exploring how monkeys survive in a landscape increasingly shaped by humans. He and his colleagues recently studied the ecology of a group of mantled howler monkeys that thrive in a habitat completely altered by humans: a cacao plantation in Tabasco, Mexico. Like many varieties of coffee, cacao plants need shade to grow, so 40 years ago the landowners planted fig, monkey pod and other tall trees to form a protective canopy over their crop. The howlers moved in about 25 years ago after nearby forests were cut. This strange habitat, a hodgepodge of cultivated native and exotic plants, seems to support about as many monkeys as would a same-sized patch of wiki forest. The howlers eat the leaves and fruit of the shade trees, leaving the valuable cacao pods alone, so the farmers tolerate them. 

H. Estrada believes the monkeys bring underappreciated benefits to such farms, dispersing the seeds of fig and other shade frees and fertilizing the soil with feces. He points out that howler monkeys live in shade coffee and cacao plantations in Nicaragua and Costa Rica as well as in Mexico. Spider monkeys also forage in such plantations, though they need nearby areas of forest to survive in the long term. He hopes that farmers will begin to see the advantages of associating with wild monkeys, which includes potential ecotourism projects. “Conservation is usually viewed as a conflict between agricultural practices and the need to preserve nature, Estrada says. “We're moving away from that vision and beginning to consider ways in which agricultural activities may become a tool for the conservation of primates in human-modified landscapes.”
Questions 14-19: The reading Passage has seven paragraphs A-I.
Which paragraph contains the following information?
Write the correct letter A-I, in boxes 14-19 on your answer sheet.
Q.14. a reference of reduction in Forest inhabitant

Q.15. Only one species of monkey survived while other two species were vanished

Q.16. a reason for howler Monkey of choosing new leaves

Q.17. mention to howler Monkey’s nutrient and eating habits

Q.18. a reference of asking farmers’ changing attitude toward wildlife

Q.19. the advantage for howler Monkey’s flexibility living in a segmented habitat

Questions 20-22: Look at the following places and the list of descriptions below. Match each description with the correct place, A-E. Write the correct letter, A-E, in boxes 20-22 on your answer sheet.
List of places
A. Hacienda La Pacifica
B. Santa Rosa National Park
C. a cacao plantation in Tabasco, Mexico
D. Estacion de Biotogia Los Tuxtlas in Veracruz, Mexico
E. Amazon Basin
Q.20. howler Monkey’s benefit to the focal region’s agriculture
Q.21. Original home for all three native monkeys
Q.22. A place where Capuchins monkey comes for a better habitat

Question 23-27: Complete the sentences below. Choose NO MORE THAN TWO WORDS from the passage or each answer. Write your answer in boxes 23-27 on your answer sheet.
The reasons for Howlers monkey survive better in local region than other two species – Howlers in La Pacifica since they can feed themselves with leaf when 23_______ is not easily found – Howlers has better ability to alleviate the 24_______, which old and young trees used to protect themselves – when compared to that of spider monkeys and capuchin monkeys, the I 25_______ rate of Howlers is relatively faster (round for just every 2 years) – the monkeys can survive away from open streams and water holes as the in Guanacaste leaves howlers eat hold high content of 26_______ which ensure them to resist to continuous 27_______ in Guanacaste.

A. While it may not be possible to completely age-proof our brains, a brave new world of anti- aging research shows that our gray matter may be far more flexible than we thought. So no one, no matter how old, has to lose their mind. The brain has often been called the three-pound universe. It’s our most powerful and mysterious organ, the seat of the self, laced with as many billions of neurons as the galaxy has stars. No wonder the mere notion of an aging, failing brain—and the prospect of memory loss, confusion, and the unraveling of our personality—is so terrifying. As Mark Williams, M.D., author of The American Geriatrics Society’s Complete Guide to Aging and Health, says, “The fear of dementia is stronger than the fear of death itself.” Yet the degeneration of the brain is far from inevitable. ”  Its design features are such that it should continue to function for a lifetime,” says Zaven Khachaturian, Ph.D., director of the Alzheimer1s Association1s Ronald and Nancy Reagan Research Institute. “There’s no reason to expect it to deteriorate with age, even though many of us are living longer lives.” In fact, scientists ‘ view of the brain1s potential is rapidly changing, according to Stanford University neuroscientist Robert Sapolsky, Ph.D.
“Thirty-five years ago we thought Alzheimer1 s disease was a dramatic version of normal aging. Now we realize it1s a disease with a distinct pathology. In fact, some people simply don’t experience any mental decline, so we’ve begun to study them.” Antonio Damasio, M.D., Ph.D., head of the Department of Neurology at the University of Iowa and author of Descartes’ Error, concurs. “Older people can continue to have extremely rich and healthy mental lives.’

B. The seniors were tested in 1988 and again in 1991. Four factors were found to be related to their mental fitness: levels of education and physical activity, lung function, and feelings of self-efficacy “Each of these elements alters the way our brain functions,“ says Marilyn Albert, Ph.D. , of Harvard Medical School, and colleagues from Yale, Duke, and Brandeis Universities and the Mt. Sinai School of Medicine, who hypothesizes that regular exercise may actually stimulate blood flow to the brain and nerve growth, both of which create more densely branched neurons, rendering the neurons stronger and better able to resist disease. Moderate aerobic exercise, including long brisk walks and frequently climbing stairs, will accomplish this.

C. Education also seems to enhance brain function. People who have challenged themselves with at least a college education may actually stimulate the neurons in their brains. Moreover, native intelligence may protect our brains. It’s possible that smart people begin life with a greater number of neurons, and therefore have a greater reserve to fall back on if some begin to fail. “If you have a lot of neurons and keep them busy, you may be able to tolerate more damage to your brain before it shows,” says Peter Davies, M.D., of the Albert Einstein College of Medicine in the Bronx, New York. Early linguistic ability also seems to help our brains later in life. A recent study in the New England Journal of Medicine looked at 93 elderly nuns and examined the autobiographies they had written 60 years earlier, just as they were joining a convent. The nuns whose essays were complex and dense with ideas remained sharp into their eighties and nineties.

D. Finally, personality seems to play an important role in protecting our mental prowess. A sense of self-efficacy may protect our brain, buffeting it from the harmful effects of stress. According to Albert, there’ s evidence that elevated levels of stress hormones may harm brain cells and cause the hippocampus—a small seahorse-shaped organ that1s a crucial moderator of memory—to atrophy. A sense that we can effectively chart our own course in the world may retard the release of stress hormones and protect us as we age. “It’ s not a matter of whether you experience stress or not, ” Albert concludes, “it’s your attitude toward it. ” Reducing stress by meditating on a regular basis may buffer the brain as well. It also increases the activity of the brain’ s pineal gland, the source of the antioxidant hormone melatonin, which regulates sleep and may retard the aging process. Studies at the University of Massachusetts Medical Center and the University of Western Ontario found that people who meditated regularly had higher levels of melatonin than those who took 5-milligram supplements Another study, conducted jointly by Maharishi International University, Harvard University, and the University of Maryland, found that seniors who meditated for three months experienced dramatic improvements in their psychological well-being, compared to their non-meditative peers.

E. Animal studies confirm that both mental and physical activity boost brain fitness. At the Beckman Institute for Advanced Science and Technology in Urbana, Illinois， psychologist William Greenough, Ph. D., let some rats play with a profusion of toys. These rodents developed about 25 percent more connections between their neurons than did rats that didn’t get any mentally stimulating recreation. In addition, rats that exercised on a treadmill developed more capillaries in specific parts of their brains than did their sedentary counterparts. This increased the blood flow to their brains. “Clearly the message is to do as many different flyings as possible,” Greenough says.

F. It’s not just scientists who are catching the anti-aging fever. Walk into any health food store, and you111 find nutritional formulas —with names like Brainstorm and Smart ALEC—that claim to sharpen mental ability. The book Smart Drugs & Nutrients, by Ward Dean, M.D., and John Morgenthaler, was self-published in 1990 and has sold over 120,000 copies worldwide. It has also spawned an underground network of people tweaking their own brain chemistry with nutrients and drugs—the latter sometimes obtained from Europe and Mexico. Sales of ginkgo —an extract from the leaves of the 200-million-year-old ginkgo tree, which has been shown in published studies to increase oxygen in the brain and ameliorate symptoms of Alzheimer‘ s disease—are up by 22 percent in the last six months alone, according to Paddy Spence, president of SPINS, a San Francisco-based market research firm. Indeed, products that increase and preserve mental performance are a small but emerging segment of the supplements industry, says Linda Gilbert, president of Health Focus, a company that researches consumer health trends. While neuroscientists like Khachaturian liken the use of these products to the superstition of tossing salt over your shoulder, the public is nevertheless gobbling up nutrients that promise cognitive enhancement.
Questions 28-31: Choose the FOUR correct letters among A-G.
Write your answers in boxes 28-31 on your answer sheet.
Which of the FOUR situations or conditions assisting the Brains’ function?
A. Preventive treatment against Alzheimer’s disease
B. Doing active aerobic exercise and frequently climbing stairs
C. High levels of education
D. Early verbal or language competency training
E. Having more supplements such as ginkgo tree
F. Participate in a more physical activity involving in stimulating tasks
G. Personality and feelings of self-fulfillment

Questions 32-39: Use the information in the passage to match the people (listed A-G) with opinions or deeds below. Write the appropriate letters A-G in boxes 32-39 on your answer sheet.
NB  You may use any letter more than once
A. Zaven Khachaturian
B. William Greenough
C. Marilyn Albert
D. Robert Sapolsky
E. Linda Gilbert
F. Peter Davies
G. Paddy Spence
Q.32. Alzheimer’s was probably a kind of disease rather than a normal aging process.
Q.33. Keeping neurons busy, people may be able to endure more harm to your brain
Q.34. Regular exercises boost blood flow to the brain and increase anti-disease disability.
Q.35. Significant increase in Sales of ginkgo has been shown.
Q.36. More links between their neurons are found among stimulated animals.
Q.37. Effectiveness of the use of brains supplements products can be of little scientific proof.
Q.38. Heightened levels of stress may damage brain cells and cause part of the brain to deteriorate.
Q.39. Products that upgrade and preserve mental competence are still a newly developing industry.

Question 40: Choose the correct letters among A-D.
Write your answers in box 40 on your answer sheet.
According to the passage, what is the most appropriate title for this passage?
A. Making our minds last a lifetime
B. amazing pills of the ginkgo
C. how to stay healthy in your old hood
D. more able a brain and neurons