1、专业英语八级(阅读)模拟试卷 109及答案与解析 SECTION A MULTIPLE-CHOICE QUESTIONS In this section there are several passages followed by fourteen multiple-choice questions. For each multiple-choice question, there are four suggested answers marked A , B, C and D. Choose the one that you think is the best answer. 0 (1)Ho
2、w living creatures evolve has been pretty well understood for the past 150 years. How they came to exist in the first place, though, remains a mystery. Part of the reason for this mystery is that subsequent evolution has done a good job of erasing the evidence. But not a complete one. Some features
3、are shared by all organisms, and may thus go back to the beginning of life. And one of the most bizarre of these features is that a lot of the molecules of which life is made are left-handed. (2)A left-handed molecule is one that causes polarized light to rotate to the left(i.e., anticlockwise). Mos
4、t molecules which behave this way have a right-handed equivalent that is, in its arrangement of atoms, their mirror image. Ordinary chemical processes cannot tell the difference between the two forms, so they are usually equally abundant. But the enzymes that govern biochemistry are such precise too
5、ls that, often, only one-handedness is acceptable. In the case of amino acids, the subunits of which proteins are made, the acceptable form is the sinister one. Many people feel that understanding why this is so would illuminate the origin of life and two groups of researchers, pursuing separate lin
6、es of enquiry, have come up with what may be the pieces of the jigsaw. (3)One further puzzle is that the amino acids found in meteorites(which are assumed to be similar to those of the primitive Earth)have been modified by a process called methylation into a form that is biologically useless. Nevert
7、heless, since such methylated amino acids are the starting point, it is where Ronald Bres-low and his student Mindy Levine, who work at Columbia University, started. (4)A couple of years ago they revealed the first piece of the jigsaw when they found that an initial imbalance in favor of left-handed
8、 methylated amino acids in a solution can be amplified by repeated evaporation. During evaporation, the left-and right-handed molecules mate up and fall out of solution, leaving a left-handed excess. A mere two cycles of evaporation can push a starting ratio that is just 1% in favor of the left to o
9、ne that is 90% left-handed. (5)Now, as Dr. Breslow has revealed to a meeting of the American Chemical Society, in New Orleans, Ms. Levine has discovered a process that favors the production of left-handed biologically active amino acids. The presence of copper in solutions that contain the chemical
10、precursors of amino acids, together with left-handed methylated amino acids to seed the reaction, gives amino-acid formation a sinister bias. When Ms. Levine made an amino acid called phenylalanine this way she got 37% more of me left-handed form than the right-handed. With another, valine, the exce
11、ss was 23% and with alanine, 20%. (6)The connection between the two pieces of work is that the left-handed methylated amino acids required to seed the second could have been provided by the evaporative process of the first if, of course, a slightly biased supply of them had previously existed. (7)Th
12、is is where Sandra Pizzarello of Arizona State University comes in. She has shown that the methylated amino acids found in meteorites do, indeed, have a bias of 1% or more in favor of the left-handed, suggesting that methylated amino acids kicking around on the primitive Earth would have shared a si
13、milar bias. (8)The mistake previous researchers made, therefore, was thinking of the methylated amino acids of meteorites as ingredients of life. Actually, if this work is pointing in the right direction, they were merely seeds. Taken together, these results argue that life formed in places with a l
14、ot of evaporation going on(suggesting heat)and a significant amount of copper present. This is speculation, of course, but it favors the idea that living things were created in land-locked ponds, rather than at sea, and probably in a volcanic environment.(Volcanic heat would drive the chemical react
15、ions, as well as causing lots of evaporation.)It also suggests that biochemical left-handedness confers no selective advantage. What makes meteoritic amino acids left-handed has yet to be discovered. But it seems just a matter of chance that the living world is sinister. 1 What can be inferred from
16、the results of the studies by Ronald Breslow and Mindy Levine? ( A) Repeated evaporation pushes the right-handed molecules out completely. ( B) The simple presence of copper in the solutions gives amino-acid formation a sinister bias. ( C) The result of the first study has seeded the reaction of the
17、 second study. ( D) The two pieces of work connect in that they both created left-handed amino acid. 2 Sandra Pizzarello suggests that methylated amino acids found in meteorites _. ( A) are ingredients of life ( B) have a bias for left-handedness ( C) are the origin of life ( D) have the same bias a
18、s the ones on the primitive Earth 3 From the description in the passage, we learn that _. ( A) evidence of evolution has been completely erased, leaving the origin of life a mystery ( B) most of enzymes that govern biochemistry are left-handed ( C) the results point out that the methylated amino aci
19、ds of meteorites are the seeds of life ( D) the results argue that evaporation and copper are important in the formation of life 3 (1)Too often, investors focus on figures that supposedly offer insight into a companys performance without shedding light on how it actually makes its money. (2)Graphic-
20、design and printing-services company VistaPrint is a case in point. Investors have pushed the shares down over the past month because the companys most recent quarterly results raised concerns about slowing revenue growth and narrowing gross margins. (3)But on that score, investors may be worrying a
21、bout the wrong issue: VistaPrint appears to generate a big portion of its operating profit from fees it receives for “referring“ customers to outside parties that “offer“ rewards programs. (4)That calls into question whether the stock, even after its recent fall, deserves to trade at 20 times expect
22、ed earnings for the fiscal year ending in June 2009, according to estimates from Thomson Reuters. (5)VistaPrints customers often dont realize that they are purchasing the referred services. The services are offered through a screen that pops up at the end of the VistaPrint buying process. That scree
23、n purports to offer the customer $10 off their most recent purchase. But customers who sign up for this are actually enrolling in a program that charges them $14.95 a month for what are supposed to be discounts on amusement parks and movies, among other things. (6)In a statement, VistaPrint said, “W
24、e dont trick our customers into a service that they dont want. Customers are smarter than that. We go to great lengths to ensure that only those customers that want that particular service or offering pay for that service or offering.“ (7)The company declined to say what portion of operating profit
25、comes from referral fees, adding that it doesnt give product-by-product breakdowns. (8)In regulatory filings, VistaPrint acknowledges the risk associated with referral fees. The company said some of the programs that pay it referral fees “have been the subject of consumer complaints and litigation a
26、lleging that their enrollment and billing practices violate various consumer protection laws or are otherwise deceptive.“ (9)A careful read of the fine print in VistaPrints financial filings shows that referral fees are an important driver of profit. (10)In the fiscal quarter ended March 31, VistaPr
27、int said 6.7% of its $106 million in revenue came from referral fees. Such disclosures about referral fees came only after prodding last year from the Securities and Exchange Commission. (11)But the SEC didnt force VistaPrint to disclose how this revenue affected operating profit. To figure that out
28、, one has to read lower in the footnote, which says that referral-fee revenues “have minimal corresponding direct cost of revenue.“ (12)In other words, they are pretty much pure profit. But assuming, say, that the company racked up an 80% margin on these revenues, me fees would have accounted for ab
29、out half of operating profit in me most recent quarter. (13)The contribution, though, could be even higher, given VistaPrints own description of me costs tied to mem as “minimal“. Analysts note mat referral revenue is declining as an overall slice of me business. But it still makes up a big piece of
30、 profit. (14)Until that changes, investors should remember mat VistaPrint prints business cards not money. 4 According to the passage, VistaPrint is a company that_. ( A) sells graphic and printing products ( B) offers rewards programs to customers ( C) has undergone dropping share prices over the p
31、ast month ( D) has had narrow gross margins in the most recent quarter 5 The relationship between the ninth and tenth paragraphs is that_. ( A) each presents one side of companys performance ( B) me ninth generalizes and the tenth specifies it ( C) me tenth is the logical result of the ninth ( D) bo
32、th illustrate VistaPrints driver of profit 6 The authors attitude towards the referral fees that VistaPrint receives is _. ( A) positive ( B) neutral ( C) negative ( D) unknown 7 Which of the following is NOT true, according to the passage? ( A) VistaPrint refers its customers to outside parties and
33、 receives referral fees for that. ( B) Referral revenue makes up half of VistaPrints revenue and its still growing. ( C) Referral fees have brought about complaints and litigation to VistaPrint. ( D) VistaPrint spends virtually no cost to earn the referral-fee revenues. 7 (1)Greece is a land of rugg
34、ed mountains, shady olive trees, more varieties of wildflowers man any other European country, and islands scattered like jewels across a brilliant blue sea. According to ancient mythology, in a war between gods, the Titans tore the tops from mountains, using them as weapons. The rocky peaks fell in
35、to the sea, thus creating the many islands of Greece. Mymology, history, and folklore have shaped me way people think in this ancient land; me land itself has shaped their way of life. (2)Greece is believed to have been first settled around 3000 B.C., when invaders swept down from me north. They fai
36、led to reach me island of Crete, home of me Minoans. A literate, advanced civilization with its own hieroglyphic style of writing, me Minoans lived in luxurious cities and palaces. They even had flush toilets, hot and cold running water, and thermal heating. In 1400 B.C., a volcanic eruption on the
37、nearby island of Thera caused earthquakes and tidal waves mat destroyed the Minoan civilization. Mainland Greece became the major Mediterranean sea power. (3)Around 1200 B.C., the Greeks began forming city-states called polis. Each had its own rulers, army, and individual type of government. Our own
38、 democracy is based on the style of government Athens had at that time. (4)The Classical Period began in the fifth century B.C. Although Greece led the world in science, culture, and the arts, the city-states fought violently among themselves. In 338 B.C., Philip of Macedonia conquered the Greek cit
39、y-states. His son, Alexander the Great, enlarged the empire, introducing Greek culture to the lands he conquered. (5)Over the next 2,000 years, from 145 B.C. onward, Romans, Byzantines, and Ottoman Turks ruled Greece in succession. Although Greece gained its independence from Turkey in 1830, other o
40、utsiders invaded Greece; within the country, there was unrest among the Greeks themselves. Finally, in 1974, Greece rejected its military government and monarchy and became a democratic republic. (6)Greece is divided into regions and island groups. The landscape has always shaped its people, the way
41、 they live, where they live, and the type of work they do. No one lives more than 60 miles from the sea Because of the rugged terrain and dry, rocky soil, agriculture is restricted to one third of the land. Transportation is difficult, and more than nine thousand islands, “flowers of marble“ are sca
42、ttered across three seas the Mediterranean, Ionian, and Aegean. Only 169 of these islands are inhabited. (7)Farmland is limited, yet half of the Greek population works in agriculture. For a long time, agricultural produce such as olives, figs, raisins, tobacco, sugar, and wheat were the countrys mos
43、t valuable assets. The bare, rocky land is perfect for growing olive trees. Farms, however, are small. Often three generations share both a home and the farm chores. Today, the government is encouraging farmers to specialize. Exporting the additional produce would provide added revenue for Greece. (
44、8)Greece has some of the worlds richest ship owners; its merchant fleet is the sixth largest in the world. In villages along the coast and on the islands, a great many other Greeks earn their living from the sea. Using open, single-mast wooden fishing boats known as caiques, whole families are invol
45、ved with the sea. Once, sponge fishing was a vital industry. Unfortunately, as more people buy man-made, less expensive sponges, the market for natural sponges is dying out. (9)Many Greeks work in the tourist industry. Spectacular historic sites abound on the mainland, while the islands, in particul
46、ar, draw people from all over the world. In summer, ferries constantly ply the waters among them. Many of the islands have beautiful beaches, windmills and snow-white streets like pictures. Some, such as Mikonos, are golden and dry; others, such as Corfu, are green and tree filled. The sun is hot, t
47、he sky a clear, sparkling blue. (10)The climate, a combination of Mediterranean(warm wet winters and hot dry summers)and European(hot, muggy summers and cold snowy winters), affects all three industries agriculture, fishing, and tourism. Athens can be 100 degrees Fahrenheit in the shade in July and
48、August. In summer, melterni, or strong winds, cause rough seas, affecting both fishing and ferryboats. (11)One third of the population lives and works in the bustling, modern, capital city of Athens. However, in rural Greece, particularly the more remote villages, the traditional way of life has not
49、 changed for centuries. Donkeys are still an important means of transportation, everyone knows everyone else, the older women swathe themselves from head to toe in black In the evenings, people gather at tables and chairs in the main square to chat, sip ouzo(an anise drink), or play backgammon. For centuries, father time has stood still in this beautiful country. 8 Which of the following is NOT true about the Classical Period of Greece? ( A) Greece had advanced science, culture, and the arts. ( B) The empire witnessed violent fights am
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