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　　PartⅡ Reading Comprehension (Skimming and Scanning)(15 minutes)

　　Main Energies for the Body

　　A balanced diet is one that provides an adequate intake of energy and nutrients for maintenance of the body and therefore good health. A diet can easily be adequate for normal bodily functioning, yet may not be a balanced diet.

　　Carbohydrates

　　Carbohydrates are a rapid source of energy, they are the body's fuel. The bulk of a balanced diet should be made from carbohydrates. If eaten in an excess of the dietary requirements carbohydrates are easily stored as fats in the cells, although carbohydrate is the first source of energy in the body. An average adult requires about 12,000kJ of energy a day, most of this is supplied by the respiration of carbohydrates in the cells.

　　Carbohydrates are used principally as a respiratory substrates, i.e. to be oxidized to release energy for active transport, macromolecule synthesis, cell division and muscle contraction. Carbohydrates are digested in the duodenum and ileum and absorbed as glucose into cells. Sources of carbohydrates such as starch are rice, potatoes, wheat and other cereals. Sugars are also carbohydrates, sources of sugars are refined sugar - sucrose, which is a food sweetener and preservative and fruit sugars - fructose. If the diet lacks carbohydrate stores of fat are mobilized and used as an energy source.

　　Proteins

　　Protein is not a direct source of energy in the body, it is used primarily for growth and repair of body tissues while remaining an energy source as a last resort. Proteins fulfill a wide variety of roles in the body. They are broken down in the stomach and intestines to amino acids which are then absorbed. The body can only form 8 amino acids to build proteins from, the diet must provide Essential Amino Acids (EAAs) which are synthesized into proteins which can be structural, i.e. collagen in bone, keratin in hair, myosin and actin in muscle; metabolic enzymes, hemoglobin, protective antibodies and communicative hormones.

　　Sources of protein include meat, fish, eggs and pulses. The diet needs to provide 8 EAAs as the body is unable to synthesis proteins without these molecules. 2 other amino acids are synthesized from EAAs so if the diet lacks the original EAAs these other two will not be present either. Phenylalanine is converted to tyrosine and methionine is converted to cysteine. Cells draw upon a pool of amino acids for protein synthesis which either come from dietary protein digested and absorbed in the gut and the breakdown of body protein such as muscle. However, unlike fats and carbohydrates there is no store of amino acids for cells to draw on, any amino acid in excess of immediate bodily requirements is broken down into urea and excreted. It is therefore important to maintain the dietary intake of protein everyday. If the body lacks protein, muscle wasting occurs as muscle is broken down.

　　If protein is lacked in a diet a person develops kwashiorkor which is caused when high levels of carbohydrates are eaten to overcome the lack of protein in the diet. One symptom of kwashiorkor is the abnormal collection of fluid around the abdomen due to the lack of protein in the blood. The body cannot retain water by osmosis and fluid accumulates in tissues causing them to become waterlogged.

　　Vitamin Categories

　　Vitamins cannot be synthesized by the body so must be supplied by diet. Vitamins have no common structure or function but are essential in small amounts for the body to be able to utilize other dietary components efficiently.

　　Vitamins fall into two categories, fat soluble vitamins such as vitamin A, D, E and K which are ingested with fatty foods and water soluble vitamins such as the B group vitamins and vitamin C. Vitamins are known as micronutrients because only small quantities are required for a healthy diet, in fact fat soluble vitamins can be toxic in high concentrations, for example the body stores vitamin A, or retinol, in the liver as it is toxic if kept in high concentrations in the blood stream, a dose of more than 3300mg of vitamin A can be considered toxic. Water soluble vitamins such as vitamin C and B groups vitamins can be excreted in the urine if in excess in the diet.

　　Vitamins A

　　Vitamin A is essential to the proper functioning of the retina in the eye and the epithelial tissues. A lack of vitamin A results in dry, rough skin, inflammation of the eyes, a drying or scarring of the cornea - xerophthalmia, which occurs when the secretion of lubricating tears is stopped, the eyelids become swollen and sticky with pus. Mucous surfaces of the eye may become eroded allowing infection to set in, leading to ulceration and destruction of the cornea. Night blindness - an inability to see in dim light can also occur. Rod cells in the retina of the eye detect light of low intensity, they convert vitamin A into a pigment, rhodopsin, which is bleached when light enters the eye. Rod cells resynthesis rhodopsin, but if there is a deficiency of the vitamin, rod cells can no longer function and the result is night blindness. Epithelial cells use retinol to make retinoic acid, an intracellular messenger used in cell differentiation and growth. Without retinoic acid epithelial cells are not maintained properly and the body becomes susceptible to infections, particularly measles and infections of the respiratory system and gut.

　　Xenophthalmia is common among children who's diets consist of mainly cereals with little meat or fresh vegetables, this is common in Indonesia, Bangladesh, India and the Philippines.

　　Vitamins D

　　Vitamin D, or calciferol, is another fat soluble steroid vitamin which functions to stimulate calcium uptake from the gut and its deposition in bone. vitamin D acts as a hormone when converted by enzymes in the gut and liver into an active form of "active vitamin D", which stimulates epithelial cells in the intestine to absorb calcium. vitamin D is therefore essential in growing children's diets to enable the growth of strong bones. Without adequate amounts of vitamin D children can develop rickets, which is the deformation of the legs caused when they lack calcium to strengthen the bones. In adults a lack of vitamin D in the diet can lead to osteomalacia, a progressive softening of the bones which can make them highly susceptible to fracture.

　　Vitamin D is made by the body when exposed to sunlight and is stored in the muscles, however, if the skin is rarely exposed to the sunlight or is dark little vitamin D is produced. Foods such as eggs and oily fish are all rich in vitamin D.

　　Vitamins K

　　Vitamin K, phylloquinone, is found in dark green leafy vegetables such as spinach and kale. It is a fat soluble vitamin which is involved in the clotting process of blood. In the intestines bacteria synthesize a number of important clotting factors which need vitamin K. Without vitamin K cuts can fail to heal and internal bleeding can occur.

　　Vitamins C

　　Vitamin C is a water soluble vitamin, known chemically as ascorbic acid. It is found in citrus fruits such as oranges and lemons, and also in potatoes and tomatoes. The main function of vitamin C is the formation of connective tissues such as collagen. It is also known to be an antioxidant which helps to remove toxins and aids the immune system. A lack of vitamin C leads to Scurvy, a condition experienced by sailors on long journeys when they did not have fruit in their diets. Scurvy causes painful, bleeding gums. As vitamin C is water soluble, it is not toxic in high doses as it can be excreted in the urine, very high doses can however cause diarrhea.

　　Vitamins B

　　B group vitamins have a wide range of roles acting as co-enzymes in metabolic pathways. They are found in most plant and animal tissues involved in metabolism, therefore foods such as liver, yeast and dairy products are all rich in B group vitamins. Deficiency of B group vitamins include dermatitis, fatigue and malformation of red blood cells.

　　1. An adult needs about 12,000kJ of energy a day from ________.

　　A. the cell

　　B. the respiring process of carbohydrates

　　C. fats in the cell

　　D. a balanced diet

　　2. Carbohydrates are ultimately absorbed into cells in the process of _______.

　　A. digestion

　　B. respiration

　　C. oxidization

　　D. mobilization

　　3. The Essential Amino Acids which build part of proteins can be obtained from______.

　　A. stomach

　　B. body tissues

　　C. the body

　　D. the diet

　　4. The ultimate cause of kwashiorkor is lack of ________.

　　A. protein

　　B. carbohydrates

　　C. vitamins

　　D. diet

　　5. Vitamins are called “micronutrients” in that _________.

　　A. excessive fat soluble vitamins can be excreted in the urine

　　B. the body only requires small amount of vitamins

　　C. a dose of 3300mg of vitamins can be considered toxic

　　D. the high concentrations of water soluble vitamins are toxic

　　6. Night blindness is a disease normally caused by lack of __________.

　　A. fat soluble vitamins

　　B. water soluble vitamins

　　C. vitamin A

　　D. innate disability

　　7. The main function of vitamin D is to prevent adults from ________.

　　A. the growth of strong bones

　　B. fracture

　　C. a progressive softening of the bones

　　D. calcium uptake from the gut

　　8. Although the human body produces vitamin D normally, it fails to do so if there is not enough ______________.

　　9. The reason why vitamin C is seen as an antioxidant is that it drives __________ out of the body.

　　10. If you are in lack of B group vitamins, you should turn to _______________.

　　Part Ⅳ Reading Comprehension (Reading in Depth) (25 minutes)

　　Section A

　　Directions：In this section，there is a short passage with 5 questions or incomplete statements. Read the passage carefully. Then answer the questions or complete the statements in the fewest possible words on Answer Sheet 2.

　　Questions 47 to 51 are based on the following passage.

　　For most people, shopping is still a matter of wandering down the high street or loading a cart in a shopping mall. Soon, that will change. Electronic commerce is growing fast and will soon bring people more choices. There will, however, be a cost: protecting the consumer from fraud will be harder. Many governments therefore want to extend highstreet regulations to the electronic world. But politicians would be wiser to see cyberspace as a basis for a new era of corporate self-regulation.

　　Consumers in rich countries have grown used to the idea that the government takes responsibility for everything from the stability of the banks to the safety of the drugs, or their rights to refund(退款) when goods are faulty. But governments cannot enforce national laws on businesses whose only presence in their country is on the screen. Other countries have regulators, but the rules of consumer protection differ, as does enforcement. Even where a clear right to compensation exists, the online catalogue customer in Tokyo, say, can hardly go to New York to extract a refund for a dud purchase.

　　One answer is for governments to cooperate more: to recognize each other’s rules. But that requires years of work and volumes of detailed rules. And plenty of countries have rules too fanciful for sober states to accept. There is, however, an alternative. Let the electronic businesses do the “regulation” themselves. They do, after all, have a self-interest in doing so.

　　In electronic commerce, a reputation for honest dealing will be a valuable competitive asset. Governments, too, may compete to be trusted. For instance, customers ordering medicines online may prefer to buy from the United States because they trust the rigorous screening of the Food and Drug Administration; or they may decide that the FDA’s rules are too strict, and buy from Switzerland instead.

　　Consumers will need to use their judgment. But precisely because the technology is new, electronic shoppers are likely for a while to be a lot more cautious than consumers of the normal sort---and the new technology will also make it easier for them to complain noisily when a company lets them down. In this way, at least, the advent of cyberspace may argue for fewer consumer protection laws, not more.

　　注意：此部分试题请在答题卡2上作答。

　　47. What can people benefit from the fast-growing development of electronic commerce?

　　48. When goods are faulty, consumers in rich countries tend to think that it is ______________ who takes responsibility for everything.

　　49. In the author’s view, why do businesses place a high premium on honest dealing in the electronic world?

　　50. People may turn to _______________ in that FDA has too strict rules.

　　51. _____________are probably more cautious than consumers of the normal sort when buying things.

　　Passage Two

　　Questions 26 to 30 are based on the following passage.

　　The importance of symbols as a source of cultural diversity can be seen in the dress codes and hairstyles of different societies. In most situations, the symbolism of clothing and hairstyles communicates different messages ranging from political beliefs to identification with specific ethnic or religious groups. The tartan(格子呢) of a Scottish clan, the black leather jacket and long hair of a motorcycle gang member in the United States, and the veil of an Islamic woman in Saudi Arabia provide a symbolic vocabulary that creates cultural diversity.

　　Many examples of clothing styles could be used to illustrate how symbols are used to produce cultural diversity. Consider, for instance, changing dress codes in the United States. During the 1960s, many young people wore jeans, sandals, and beads to symbolize their rebellion against what they conceived as the conformist inclinations of American society. By the 1980s, many of the same people were wearing “power suits” as they sought to advance up the corporate ladder.

　　An example of how hairstyles can create meaningful symbolic codes can be seen in a group known as the Rastafarians(sometimes known as Rastas or Rastaman) of Jamaica. The majority of the people of Jamaica are of African descent. During the eighteenth and nineteenth centuries, they were brought to Jamaica by European slave traders to work on plantations. The Rastafarians are a specific religious group within Jamaica who believe that Haile Selassie(1892-1975), the former emperor of Ethiopia, whose original name was Ras Tafari, was the black Messiah who appeared in the flesh for the redemption of all blacks exiled in the world of white oppression. Rastafarian religion fuses Old Testament teachings, Christian mysticism, and Afro-Jamaican religious beliefs. The Rastafarian movement originated as a consequence of harsh economic, political, and living conditions in the slums of Jamaica.

　　In the 1950s, during the early phase of the Rastafarian movement, some male members began to grow their hair in “locks” or “dreadlocks” to symbolize their religious and political commitments. This hairstyle became well known in Western society through reggae(强节奏黑人音乐) music and Rasta musicians such as the late Bob Marley. Rastafarians derive the symbolism of the dreadlock hairstyle of the Rastafarians from the Bible. They view the unshaven man as the natural man and invoke Samson as one of the most important figures in the Bible. Dreadlocks also reflect a dominant symbol within the Rastafarian movement, the lion, which is associated with Haile Selassie, one of whose titles was the “Conquering Lion of Judah(犹大).”To simulate the spirit of the lion, some Rastas do not cut their hair, sometimes growing their locks 20 inches or more.

　　Thus, to a great extent, culture consists of a network of symbolic codes that enhance values, beliefs, worldviews, and ideologies within a society, Humans go to a great length to create symbols that provide meaning for individuals and groups. These symbolic meanings are a powerful source of cultural diversity.

　　52.What is the main idea of this selection?

　　A.Hairstyles and dress codes identify political beliefs in diverse societies.

　　B.The Rastafarian movement symbolized a religious and political commitment.

　　C.Symbols provide meaning and a satisfaction of biological needs in society.

　　D.Hairstyles and dress codes can be important symbols of cultural diversity in different societies.

　　53.The author uses the examples of the Scottish tartan, the motorcycle jacket, and the Islamic veil to show .

　　A.the political power of dress codes in different societies

　　B.the diversity of clothing styles throughout the world

　　C.dress codes that symbolize different ethnic and religious groups

　　D.the resistance to change of culturally different groups

　　54.The author suggests that the young people wearing jeans in the 1960s wore “power suits” in the 1980s because .

　　A.styles changed B.the American government changed

　　C.their attitudes and goals changed D.both outfits symbolized rebellion

　　55.All of the following are true of the Rastafarians EXCEPT .

　　A.they believe that Emperor Haile Selassie was the black Messiah

　　B.they are the original natives of Jamaica

　　C.they are a religious group with political commitments

　　D.they formed as a result of harsh living conditions in Jamaica

　　55.The Rastafarian movement began .

　　A.at the beginning of the nineteenth century

　　B.around the middle of the twentieth century

　　C.before European slave traders arrived

　　D.in the early eighteenth century

　　Passage Three

　　Questions 31 to 35 are based on the following passage.

　　Age has its privileges in America, and one of the more prominent of them is the senior citizen discount. Anyone who has reached a certain age — in some cases as low as 55 — is automatically entitled to dazzling array of price reductions at nearly every level of commercial life. Eligibility is determined not by one’s need but by the date on one’s birth certificate. Practically unheard of a generation ago, the discounts have become a routine part of many businesses — as common as color televisions in motel rooms and free coffee on airliners.

　　People with gray hair often are given the discounts without even asking for them; yet, millions of Americans above age 60 are healthy and solvent(有支付能力的). Businesses that would never dare offer discounts to college students or anyone under 30 freely offer them to older Americans. The practice is acceptable because of the widespread belief that “elderly” and “needy” are synonymous(同义的). Perhaps that once was true, but today elderly Americans as a group have a lower poverty rate than the rest of the population. To be sure, there is economic diversity within the elderly, and many older Americans are poor. But most of them aren’t.

　　It is impossible to determine the impact of the discounts on individual companies. For many firms, they are a stimulus to revenue. But in other cases the discounts are given at the expense, directly or indirectly, of younger Americans. Moreover, they are a direct irritant in what some politicians and scholars see as a coming conflict between the generations.

　　Generational tensions are being fueled by continuing debate over Social Security benefits, which mostly involves a transfer of resources from the young to the old. Employment is another sore point. Buoyed(支持)by laws and court decisions, more and more older Americans are declining the retirement dinner in favor of staying on the job — thereby lessening employment and promotion opportunities for younger workers.

　　Far from a kind of charity they once were, senior citizen discounts have become a formidable economic privilege to a group with millions of members who don’t need them.

　　It no longer makes sense to treat the elderly as a single group whose economic needs deserve priority over those of others. Senior citizen discounts only enhance the myth that older people can’t take care of themselves and need special treatment; and they threaten the creation of a new myth, that the elderly are ungrateful and taking for themselves at the expense of children and other age groups. Senior citizen discounts are the essence of the very thing older Americans are fighting against — discrimination by age.

　　56. We learn from the first paragraph that _______.

　　A ) offering senior citizens discounts has become routine commercial practice

　　B ) senior citizen discounts have enabled many old people to live a decent life

　　C ) giving senior citizens discounts has boosted the market for the elderly

　　D ) senior citizens have to show their birth certificates to get a discount

　　57. What assumption lies behind the practice of senior citizen discounts?

　　A ) Businesses, having made a lot of profits, should do something for society in return.

　　B ) Old people are entitled to special treatment for the contribution they made to society.

　　C ) The elderly, being financially underprivileged, need humane help from society.

　　D ) Senior citizen discounts can make up for the inadequacy of the Social Security system.

　　58. According to some politicians and scholars, senior citizen discounts will _____.

　　A ) make old people even more dependent on society

　　B ) intensify conflicts between the young and the old

　　C ) have adverse financial impact on business companies

　　D ) bring a marked increase in the companies’ revenues

　　59. How does the author view the Social Security system?

　　A ) It encourages elderly people to retire in time.

　　B ) It opens up broad career prospects for young people.

　　C ) It benefits the old at the expense of the young.

　　D ) It should be reinforced by laws and court decisions.

　　60. Which of the following best summarizes the author’s main argument?

　　A ) Senior citizens should fight hard against age discrimination.

　　B ) The elderly are selfish and taking senior discounts for granted.

　　C ) Priority should be given to the economic needs of senior citizens.

　　D ) Senior citizen discounts may well be a type of age discrimination.