IELTS PRACTICE TESTS READING TEST 14 IELTS-PRACTICE-TESTS.com Pra ctice Test / Rea ding Good Luck! 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and you will be considered to have accepted such changes if you use this web site after we have published the changed terms on this web site If you have any questions about this document or our privacy policy, please contact us © IELTS-PRACTICE-TESTS.com , All Rights Reserved This content is for your ow n individua l study only You ca nnot sha re or tra nsm it it Non com plia nce could result in lega l a ction a ga inst you IELTS-PRACTICE-TESTS.com Pra ctice Test / Rea ding Reading Academic IELTS-PRACTICE-TESTS.com Test 14 IELTS-PRACTICE-TESTS.com © IELTS-PRACTICE-TESTS.com , All Rights Reserved This content is for your ow n individua l study only You ca nnot sha re or tra nsm it it Non com plia nce could result in lega l a ction a ga inst you IELTS-PRACTICE-TESTS.com SECTION Pra ctice Test / Rea ding Questions – 13 Thin-film solar power The modernist box that won this year's Solar Decathlon, a contest for solar-powered houses sponsored by America's Department of Energy, had solar panels of the conventional, crystalline sort on its roof But the walls were covered in solar cells made with thin coatings of silicon and other materials in the place of expensive slices of crystal Thin film, as this technology is known, is still less popular than crystalline cells and its move to the mainstream has been a year or two away for a decade But its time may have come at last There are many exotic ideas involving thin film, from the solar shingles recently unveiled by Dow, a big chemical company, a roof 's worth costs $27,000, to experimental prototypes of power-generating clothes, roads and cars However, most thin film comes in the form of panels that resemble crystalline ones They are roughly half as efficient, meaning that a panel must be twice as big to generate the same amount of power, but a third cheaper, watt for watt So in places where there is no shortage of space, they are the natural option Thin-film cells are also more versatile, since they can be mounted on a variety of materials including flexible plastics and fabrics Like all solar cells, they are becoming more efficient: the decathletes of Team Germany, who designed the winning house, bragged that its north façade was covered in panels that could convert even indirect sunlight into electricity IELTS-PRACTICE-TESTS.com Over the past year or so, thanks to a crash in demand tied to the recession and falling subsidies in big markets, the price of crystalline panels has fallen by 30-40%, undermining thin film's relative advantage Nonetheless, thin film's share of the market has continued to rise: it is now almost half, compared with just 10% in 2004 The biggest force in the industry is a firm called First Solar, based in Arizona, a sunny American state Like that of virtually all alternative-energy firms, its share price has suffered in the recession But it has nonetheless performed considerably better than Standard & Poor's clean-energy index over the past three years Its gross margins in the first half of the year were over 50%, on sales of $944m This month the firm was added to the S&P 500 stockmarket index of America's biggest firms IELTS-PRACTICE-TESTS.com First Solar looks likely to continue to grow Last month it signed a memorandum of understanding with China to install two gigawatts' worth of panels in Inner Mongolia-a place with plenty of space That is enough to power million homes Installation is due to begin next year and finish in 2019 That and other projects should consume all its output for several years to come First Solar's rivals are much smaller But technological advances may yet catapult one to the fore, says Steve Milunovich, an analyst at Bank of America Merrill Lynch First Solar makes its cells from a chemical called cadmium telluride But firms such as Nanosolar, which is building factories in California and Germany, believe that a combination of copper, indium, gallium and selenium known as CIGS will prove cheaper to produce on a mass scale Researchers at the University of California, meanwhile, hold out great hopes for cells made of organic chemicals For the moment, however, the cheapest form of solar power is none of these, but the less glamorous solar-thermal power, which involves heating water with sunlight to make steam Utilities are also keen to use lenses to increase the amount of sunlight hitting solar panels-a technique known as concentrating solar power They still need subsidies or a high price on carbon emissions to make investments in any sort of solar power profitable But the gap between solar and conventional power sources is becoming, well, thinner © IELTS-PRACTICE-TESTS.com , All Rights Reserved This content is for your ow n individua l study only You ca nnot sha re or tra nsm it it Non com plia nce could result in lega l a ction a ga inst you IELTS-PRACTICE-TESTS.com Pra ctice Test / Rea ding Questions - Write True, False or Not Given At this year's Solar Decathlon, 'thin film' covered the roof of the modernist box When space is not a problem, it's probably better to use crystalline films Team Germany's house won because of its ability to turn indirect sunlight into electricity The price reduction of crystalline films has prevented thin films from gaining market share In the last three years, First Solar's share price has increased more than Standard & Poor's clean-energy index First Solar is not yet listed on the S&P 500 IELTS-PRACTICE-TESTS.com Questions - 13 Complete the summary with NO MORE THAN TWO WORDS from the text Based on its contract with China, it seems probable that First Solar will further However, it does face competition from several sources First, there are a number of using the potentially CIGS production process In addition, 10 power, though perhaps not as 11 as the alternatives is still the cheapest And despite a narrowing 12 , solar's biggest competitor is still 13 IELTS-PRACTICE-TESTS.com © IELTS-PRACTICE-TESTS.com , All Rights Reserved This content is for your ow n individua l study only You ca nnot sha re or tra nsm it it Non com plia nce could result in lega l a ction a ga inst you IELTS-PRACTICE-TESTS.com SECTION Pra ctice Test / Rea ding Questions 14 – 26 The DNA of the domesticated horse THE genomes of many mammals have now been completed, including the cow, the dog, the chimpanzee and, of course, the human This week it was the turn of the horse to have its DNA sequence decoded With it emerged further evidence of how horses have been close human companions and, like other mammals that share an evolutionary history with man, how they could help the understanding of hereditary diseases But there was also a surprise: horses have a newly forming part in their genetic make-up which shows the evolutionary process in action in a way that has not been seen before A team of researchers led by Claire Wade, then at the Broad Institute, in Cambridge, Massachusetts, collaborated on the project, which is reported in the latest issue of Science They analysed DNA from a mare called Twilight to reveal a genome that consists of up to 2.7 billion base pairs (the “letters” in which the genetic message is written) This is slightly larger than the genome of a dog, but smaller than that of a human or a cow They also compared Twilight, a thoroughbred, with members of other horse breeds IELTS-PRACTICE-TESTS.com The surprise was found on equine chromosome 11, in the form of a developing centromere This is the nexus of a chromosome, from which its arms dangle Relatively little is known about centromeres They are difficult to analyse, not least because they contain highly repetitive DNA sequences But every chromosome has one, and they play an essential role in ensuring that when a cell divides, each daughter inherits a copy of every chromosome in the mother cell The appearance of a new centromere, therefore, lets geneticists examine the process by which new chromosomes come into existence The new horse centromere seems common to all breeds, and has not yet acquired any repetitive DNA This discovery solves one mystery: centromeres appear before repetitive DNA, rather than being caused by it And it opens more lines of research IELTS-PRACTICE-TESTS.com The equine genome also indicates how extensive crossbreeding was in horse evolution Domestication probably began 4,000-6,000 years ago, with wild horses initially being hunted for food, and then herded for the same purpose, before being harnessed to provide power and transport This was unlike the domestication of dogs, where a small number of wolves probably domesticated themselves, by cosying up to groups of people and acting as four-legged garbage-disposal units, before being selectively in-bred into the varieties seen today In horses, a large number of mares but few stallions appear to have been involved in the development of the genome, and—with the exception of thoroughbreds—there was also a lot of genetic sharing between breeds That pattern is partly a consequence of the fact that herds of horses usually contain a lot of mares guarded by a single stallion And then there was the effect of Genghis Khan and his descendants, whose armies travelled with their ponies across much of Eurasia According to Dr Wade, who is now at the University of Sydney, “war and conquest, with the horse as a means of transport, meant the genetics were spread widely” As well as developing new centromeres, chromosomes also reorder their genes during the course of evolution The researchers found that 53% of horse genes appear on their chromosomes in the same order as they in humans—in contradistinction to dogs, where the figure is 29% Since, even with this relatively low level of synteny, as the relationship is called, dogs have proved useful in the study of some human diseases, the researchers hope that the high-synteny horse could be similarly illuminating © IELTS-PRACTICE-TESTS.com , All Rights Reserved This content is for your ow n individua l study only You ca nnot sha re or tra nsm it it Non com plia nce could result in lega l a ction a ga inst you IELTS-PRACTICE-TESTS.com Pra ctice Test / Rea ding They tested this by looking for the as-yet unknown genetic mutation involved in what is called the leopard complex This afflicts spotted horses, particularly a breed called Appaloosas, with a form of night blindness similar to one that sometimes afflicts people Horses with a single copy of the gene in question (inherited from either sire or dam) have white patches that contain polka dots If they have two copies (one from each parent), they show no spots in their patches and are likely to suffer from night blindness From millions of possibilities, the researchers were able to whittle the culprit down to being one of two candidates that reside in an area of the genome that is also responsible for coat markings The dog may be man’s best friend, but his horse may thus prove to be more genetically helpful IELTS-PRACTICE-TESTS.com IELTS-PRACTICE-TESTS.com © IELTS-PRACTICE-TESTS.com , All Rights Reserved This content is for your ow n individua l study only You ca nnot sha re or tra nsm it it Non com plia nce could result in lega l a ction a ga inst you IELTS-PRACTICE-TESTS.com Pra ctice Test / Rea ding Questions 14 - 18 Which paragraph contains 14 the role of conflict in the development of horses' genes 15 the advancement of horses compared to other animals 16 a revelation about horses genetic form 17 how the discovery of the new centromere cleared up a problem 18 the relative size of a horse's genome IELTS-PRACTICE-TESTS.com Questions 19 - 22 Write NO MORE THAN TWO WORDS for each answer 19 Which comes first, repetitive DNA or centromeres? 20 Why were horses herded originally? 21 Which sex of horse has been most influential on the progression of its genome? 22 What were Genghis Khan's ponies used for? IELTS-PRACTICE-TESTS.com Questions 23 - 26 Complete the summary with NO MORE THAN TWO WORDS from the text Researchers believe that studying horses could be equally 23 as studying dogs because of the higher level of 24 horses have with humans A recent study raised this hope By a study of the genes of a certain 25 of horse, a gene responsible for 26 in humans was identified © IELTS-PRACTICE-TESTS.com , All Rights Reserved This content is for your ow n individua l study only You ca nnot sha re or tra nsm it it Non com plia nce could result in lega l a ction a ga inst you IELTS-PRACTICE-TESTS.com SECTION Pra ctice Test / Rea ding Questions 27 – 40 This thing called love A Love is many things: the protective love of a mother for her child, the passion of a couple newly in love, the deep love of long-term companions and the divine love of God, to name just a few Some cultures have 10 or more words for different forms of love, and poets and songwriters always find myriad aspects of love to celebrate Is there anything universal behind all this diversity? B The science of love is still in its infancy Yet scientists of many different disciplines are beginning to get their first insights into the nature and origin of love We can now look inside brains to view their patterns of activity, measure biochemical changes that take place in different forms of love, explore diverse human experiences of love, and look for the evolutionary roots of love in other animals C If the different forms of love have any common evolutionary beginning, where should we look? Maternal love seems a good place to start Of all the forms of love, none seems as deep, strong, selfless or enduring as the love of a mother for her child, nor is any other bond so ubiquitous in the animal kingdom Biologically this bond makes perfect sense In any animal that must provide care for newborn offspring to survive, the bond is essential if that mother's genes are to be passed on to the next generation IELTS-PRACTICE-TESTS.com D How is that bond created? Much of what we know about the brain chemistry of bonding comes from studies of rodents Whether they feel "love" we cannot say, but they will bitterly defend their young This tendency seems directly triggered by motherhood: virgin female rats, or even pregnant ones, will avoid or attack pups, but just before giving birth their behaviour changes profoundly So, what makes newborn infants so special to their mothers? The critical link turns out to be the hormone oxytocin Late in pregnancy, raised levels of oestrogen boost the number of receptors for oxytocin in parts of the brain During birth, the physical stimulation of labour triggers the release of oxytocin and when the hormone hits those receptors it causes the mother to become addicted to those pups and their particular smell "Addicted" might seem like a strong word, but the process of bonding to the newborn pups involves powerful activation of a system that carries reward information around the brain It is this same dopamine reward circuit that can be artificially stimulated by drugs like cocaine and heroin IELTS-PRACTICE-TESTS.com E The 'prize' circuits originate near the base of the brain in the ventral tegmental area (VTA) Nerve fibres from here connect to the front of the brain, most importantly to the nucleus accumbens that lies just beneath the frontal cortex, where they release the neurotransmitter dopamine Ultimately, it is in the cortex that 'prize' information is coordinated with emotions and memories and where, in humans, subjective feelings are created, but it is the VTA that sends on the key information about the value of an activity and helps stamp it into memory F When a rat is bonding to her pups, this reward system is boosted by oxytocin at the same time as the hormone facilitates sensitivity to smell, ensuring that the bonding is specific to the unique smell of the mother's own pups Every time the mother sniffs its pups again, it may sense that same feeling of impending reward, much as a drug addict feels cravings at the thought of the drug G Care of the young is even more important in the higher mammals Chimpanzees don't leave their mothers until they are more than seven years old and human children stay around far longer You might think that alongside the strengthening bond between mother and infant there should be a similar trend in © IELTS-PRACTICE-TESTS.com , All Rights Reserved This content is for your ow n individua l study only You ca nnot sha re or tra nsm it it Non com plia nce could result in lega l a ction a ga inst you IELTS-PRACTICE-TESTS.com Pra ctice Test / Rea ding another form of love - a monogamous bond between male and female parents, once again designed to ensure survival of the young Think again No such trend exists Among mammals, love them and leave them is most often the rule: fewer than per cent of mammalian species are monogamous, and there is no simple pattern that explains why it occasionally appears Surprisingly, the need for care from two parents is unlikely to be the main driving force for its evolution, as even among species that are monogamous many have fathers that never provide for their offspring H That leaves an interesting question: if monogamy is an evolutionary oddity rather than a trend, how does evolution occasionally redesign a species to behave so differently from other closely related ones? The answer seems to be that evolution stole the biochemistry and neural tricks that bond mother to infant and reinstalled them, so as to bind male and female together I That is the message from two species of vole that provide a natural experiment One species, the prairie vole, bonds extraordinarily closely to its mate In contrast, its close relative the meadow vole is promiscuous Partners mate and move on The difference between them comes down to where receptors for oxytocin and a closely related hormone, vasopressin, are located in the brain Those hormones are produced during "the extended tactile pleasures of mating" as one research paper puts it In the promiscuous meadow vole, few receptors for the vasopressin hormone are found in the dopamine reward region, but in the monogamous prairie vole the receptors are there in abundance, turning sex into a powerful reward that bonds the male to its partner IELTS-PRACTICE-TESTS.com J Small changes in a single gene determine whether there will be many vasopressin receptors in the reward region or not Larry Young and his colleagues at Emory University in Atlanta, Georgia, were able to make promiscuous meadow voles monogamous simply by injecting them with a virus that carried the prairie vole gene variant into their brain cells Just as predicted, if prairie voles are given drugs that arrest their vasopressin receptors, they become as promiscuous as meadow voles K Of course, voles aren't humans and their pair bonding can't really be called love But it is worth noting that among humans, there is considerable individual variation in the gene that controls the distribution of the receptors, although no one knows if it correlates with fidelity Oxytocin and vasopressin certainly seem important in human love When Andreas Bartels and Semir Zeki at University College London scanned the brains of couples who had been together for several years while they looked at a picture of their partner, they found that activity rose in just those parts of the brain that are rich in receptors for these two hormones IELTS-PRACTICE-TESTS.com © IELTS-PRACTICE-TESTS.com , All Rights Reserved This content is for your ow n individua l study only You ca nnot sha re or tra nsm it it Non com plia nce could result in lega l a ction a ga inst you IELTS-PRACTICE-TESTS.com Pra ctice Test / Rea ding Questions 27 - 37 Match each heading to the most suitable paragraph i A biological transfer ii The 'relationship' hormone iii Receptors in the human brain iv The movement of receptor locations v The route to reward vi Early scientific steps vii Behaviourism at play viii A lack of fidelity ix The starting point x The significance of receptor locations IELTS-PRACTICE-TESTS.com xi Love comes in many forms xii The transferability of the key genes 27 Paragraph A 28 Paragraph B 29 Paragraph C 30 Paragraph D 31 Paragraph E 32 Paragraph F 33 Paragraph G 34 Paragraph H 35 Paragraph I 36 Paragraph J 37 Paragraph K IELTS-PRACTICE-TESTS.com Questions 38 - 40 Write NO MORE THAN TWO WORDS for each answer 38 In the monogamous prairie vole, vasopressin hormone receptors are found 39 If the vasopressin receptors of prairie voles are blocked, the voles act in a way 40 Vasopressin appears to play a significant role in © IELTS-PRACTICE-TESTS.com , All Rights Reserved This content is for your ow n individua l study only You ca nnot sha re or tra nsm it it Non com plia nce could result in lega l a ction a ga inst you IELTS-PRACTICE-TESTS.com Pra ctice Test / Rea ding Answers IELTS-PRACTICE-TESTS.com IELTS-PRACTICE-TESTS.com © IELTS-PRACTICE-TESTS.com , All Rights Reserved This content is for your ow n individua l study only You ca nnot sha re or tra nsm it it Non com plia nce could result in lega l a ction a ga inst you IELTS-PRACTICE-TESTS.com Pra ctice Test / Rea ding 10 11 12 13 False False Not Given False True False grow rivals cheaper solar-thermal glamorous gap conventional power 14 15 16 17 18 19 20 21 22 23 24 25 26 F E A D B centromeres for food the female / the mare / mares transport illuminating synteny breed night blindness 27 28 29 30 31 32 33 34 35 36 37 38 39 40 xi vi ix ii v vii viii i x xii iii in abundance promiscuous human love IELTS-PRACTICE-TESTS.com IELTS-PRACTICE-TESTS.com © IELTS-PRACTICE-TESTS.com , All Rights Reserved This content is for your ow n individua l study only You ca nnot sha re or tra nsm it it Non com plia nce could result in lega l a ction a ga inst you [...]... appears to play a significant role in © IELTS- PRACTICE- TESTS.com , All Rights Reserved This content is for your ow n individua l study only You ca nnot sha re or tra nsm it it Non com plia nce could result in lega l a ction a ga inst you IELTS- PRACTICE- TESTS.com Pra ctice Test / Rea ding Answers IELTS- PRACTICE- TESTS.com IELTS- PRACTICE- TESTS.com © IELTS- PRACTICE- TESTS.com , All Rights Reserved This content... those parts of the brain that are rich in receptors for these two hormones IELTS- PRACTICE- TESTS.com © IELTS- PRACTICE- TESTS.com , All Rights Reserved This content is for your ow n individua l study only You ca nnot sha re or tra nsm it it Non com plia nce could result in lega l a ction a ga inst you IELTS- PRACTICE- TESTS.com Pra ctice Test / Rea ding Questions 27 - 37 Match each heading to the most suitable... mares transport illuminating synteny breed night blindness 27 28 29 30 31 32 33 34 35 36 37 38 39 40 xi vi ix ii v vii viii i x xii iii in abundance promiscuous human love IELTS- PRACTICE- TESTS.com IELTS- PRACTICE- TESTS.com © IELTS- PRACTICE- TESTS.com , All Rights Reserved This content is for your ow n individua l study only You ca nnot sha re or tra nsm it it Non com plia nce could result in lega l a ction... The starting point x The significance of receptor locations IELTS- PRACTICE- TESTS.com xi Love comes in many forms xii The transferability of the key genes 27 Paragraph A 28 Paragraph B 29 Paragraph C 30 Paragraph D 31 Paragraph E 32 Paragraph F 33 Paragraph G 34 Paragraph H 35 Paragraph I 36 Paragraph J 37 Paragraph K IELTS- PRACTICE- TESTS.com Questions 38 - 40 Write NO MORE THAN TWO WORDS for... study only You ca nnot sha re or tra nsm it it Non com plia nce could result in lega l a ction a ga inst you IELTS- PRACTICE- TESTS.com Pra ctice Test / Rea ding 1 2 3 4 5 6 7 8 9 10 11 12 13 False False Not Given False True False grow rivals cheaper solar-thermal glamorous gap conventional power 14 15 16 17 18 19 20 21 22 23 24 25 26 F E A D B centromeres for food the female / the mare / mares transport.. .IELTS- PRACTICE- TESTS.com Pra ctice Test / Rea ding another form of love - a monogamous bond between male and female parents, once again designed to ensure survival of the young Think again No such trend exists Among mammals,... vasopressin hormone are found in the dopamine reward region, but in the monogamous prairie vole the receptors are there in abundance, turning sex into a powerful reward that bonds the male to its partner IELTS- PRACTICE- TESTS.com J Small changes in a single gene determine whether there will be many vasopressin receptors in the reward region or not Larry Young and his colleagues at Emory University in Atlanta,