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Recombinant DNA technology allows scientists to cut segments of DNA from one type of organism and combine them with the genes of a second organism. Also called genetic engineering. Recombinant DNA technology is a method by which relatively simple organisms, such as bacteria or yeast, or even mammalian cells in culture, can be induced to make quantities of human proteins, including interferons or grow tobacco plants that produce monoclonal antibodies, and goats that secrete a clot-dissolving heart attack drug, tissue plasminogen activator (TPA), in their milk.Another facet of recombinant DNA technology involves gene therapy. The goal of this therapy is to replace defective genes, or to endow a cell with new capabilities. In 1989, the feasibility and safety of gene transfer was demonstrated when tumor-infiltrating lymphocytes (TILS) were extracted from a patient, equipped with a marker gene (so they could be tracked and monitored), and then re-injected into patients with advanced cancer. To deliver the gene into the TILS, the scientists used a virus, exploiting its natural tendency to invade cells, before being used as a vector, the virus was altered so that it could not reproduce or cause disease. This experiment demonstrated that gene-modified cells could survive for long periods in the bloodstream and in tumor deposits without harm to the patient.The earliest attempts to use genes therapeutically focused on a form of severe combined immunodeficiency disease (SCID), which is caused by the lack of an enzyme due to a single abnormal gene. The gene for this enzyme-adenosine deaminase (ADA)—is delivered into the patient's T cells by a modified retrovirus. When the virus splices its genes into those of the T cells, it simultaneously introduces the gene for the missing enzyme. After the treated T cells begin to produce the missing enzyme, they are injected back into the patient.Gene therapy is now being used with some cancer patients. TILS reinforced with a gene for the antitumor cytokine known as tumor necrosis factor (TNF) have been administered to patients with advanced melanoma, a deadly form of skin cancer. Plans are under way to engineer a cancer “vaccine” designed to improve anticancer immune responses by taking small bits of tumor from patients with cancer, outfitting the tumor cells with genes for immune cell activating cytokines such as LL2, and re-injecting these gene-modified tumors into the patient. While the thought of reintroducing a cancerous tumor into a patient seems somewhat frightening, the enhanced immune response triggered by this technique may help prevent the recurrence of cancer.1.What innate characteristic of viruses did researchers take advantage of in order to transport genes into TILS?2.According to the passage, SCID is caused by(  ).3.Why might cancer patients be leery of the prospect of a cancer “vaccine” as discussed in this passage?4.Adenosine deaminase (ADA) is transferred into the T cells of a patient via which of the following?

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Human language is the subject of endless scientific investigation, but the gestures that accompany speech are a surprisingly neglected area. It is sometimes jokingly said that the way to render an Italian speechless is to tie his wrists together, but almost everyone moves their hands in meaningful ways when they talk. Susan Goldin-Meadow of the University of Chicago, however, studies gestures carefully-and not out of idle curiosity. Introspection suggests that gesturing not only helps people communicate but also helps them to think. She set out to test this, and specifically to find out whether gestures might be used as an aid to children’s learning. It turns out, as she told the AAAS, that they can.The experiment she conducted involved balancing equations. Presented with an equation of 2+3+4=x+4 written on a blackboard, a child is asked to calculate the value of x. In the equations Dr. Goldin-Meadow always made the last number on the left the same as the last on the right; so x was the sum of the first two numbers. Commonly, however, children who are learning arithmetic will add all three of the numbers on the left to arrive at the value of x.In her previous work Dr. Goldin-Meadow had noted that children often use spontaneous gestures when explaining how they solve mathematical puzzles, so to see if these hand-movements actually help a child to think, or are merely descriptive, she divided a group of children into two and asked them to balance equations. One group was asked to gesture while doing so. A second was asked not to. Both groups were then given a lesson in how to solve problems of this sort.As Dr. Goldin-Meadow suspected, the first group learnt more from the lesson than the second. By observing their gestures she refined the experiment. Often, a child would touch or point to the first two numbers on the left with the first two fingers of one hand. Dr. Goldin-Meadow therefore taught this gesture explicitly to another group of children or, rather, she taught a third of them, taught another third to point to the second and third numbers this way and told the remainder to use no gestures. When all were given the same lesson it was found those gesturing “correctly” learnt the most. But those gesturing “incorrectly" still outperformed the non-gesturers.Gesturing, therefore, clearly does help thought. Indeed, it is so thought-provoking that even the wrong gestures have some value.1.Why does Susan Goldin-Meadow carry out such a study?2.What can we infer from the first paragraph?3.According to Susan’s study, children who learn the least may be(  ).4.The last sentence of this text probably means(  ).

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Doctors are researching the health benefits of red wine, specifically the apparently wondrous powers of resveratrol, a polyphenol that is found in the skin of grapes and is thought to prevent illness and promote longevity. This wasn’t the first time trumpeting the virtues of red wine; in 1991, it called attention to the so-called French Paradox, which assumed that the low rate of heart disease in France, despite a national diet gloriously abundant in rich foods, was due to the country’s huge consumption of red wine. That report fanned an obsessive interest in the nutritional and therapeutic properties of wine. This seems to be a particularly American fixation, and it raises an intriguing question: Why are we-Americans-so anxious to find justifications for drinking wine beyond the fact that it tastes good and we like it?Obviously, scientists aren’t investigating wine’s physiological impact because they are camouflage for the wine industry and want to encourage Americans to drink; the research is being pursued and the results disseminated because it appears that there really is a link between red wine and well-being. It is now widely recognized that moderate red wine consumption-generally defined ad one or two 5-ounce glasses a day for women and two or three for men, drunk with food-increases HDL cholesterol. The “good” cholesterol that remover fatty deposits from arteries. In addition, scientists have determined that the flavonoids in red wine have an anticoagulant effect that can help prevent blood clots leading to heart attacks.Resveratrol is also said to have a role in preventing clots and is believed to inhibit the production of LDL cholesterol-the bad kind. Resveratrol seems to be the omnipotent ingredient in red wine-a “vascular pipe-cleaner,” as Dr. Christoph Westphal and Harvard biochemist David Sinclair put it, whose research suggests that resveratrol can delay the aging process and prevent many gerontological diseases. A few years ago, scientists reported that resveratrol may discourage the onset of one such illness, Alzheimer. It is also claimed that this antioxidant can boost stamina, reduce lung inflammation stemming from chronic pulmonary disease, and help prevent cancer. In the fall of 2008, University of Pittsburgh scientists even reported that resveratrol might offer some protection against radiation poisoning.1.The author refers to the “French Paradox” (Line 4, Para 1) in order to(  ).2.The last sentence in Paragraph 1 implies (  ).  3.The author’s purpose is to (  ).  4.In the last paragraph, “Alzheime” is stated as an example of(  ).

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"Why are humans so smart?” is a question that fascinates scientists. Tadeusz Kawecki, a Biologist at the University of Fribourg, likes to turn around the question. “It’s so great to be smart.” Dr. Kawecki asks "Why have most animals remained dumb?” Dr.kawecki and like-minded scientists are trying to figure out why animals learn and why some have evolved to be better at learning than others. One reason for the difference, their research finds, is that being smart can be bad for an animal’s health. Learning is remarkably widespread in the animal kingdom. The worms are not born with an innate aversion to the dangerous bacteria. They need time to learn to tell the difference and avoid becoming sick. Dr. Dukas hypothesizes that any animal with a nervous system can learn, even in cases where scientists have failed to document learning in a species, he thinks they should not be too quick to rule it out.” "Is it because I'm not a good teacher or because the animal doesn’t learn?” Dr. Dukas asked.Although learning may be widespread among animals, Dr. Dukas wonders why they bothered to evolve it in the first place. “You cannot just say that learning is an adaptation to a changing environment,’’ he said. It is possible to adapt to a changing environment without using a nervous system to learn. Bacteria can alter behavior to help their survival. If a microbe senses a toxin, it can swim away. If it senses a new food, it can switch genes on and off to alter its metabolism.Learning also turns out to have dangerous side effects that make its evolution even more puzzling. Dr. Kawecki and his colleagues have produced striking evidence for these side effects by studying flies as they evolve into better learners in the lab. Dr. Kawecki suspects that each species evolves until it reaches an equilibrium between the costs and benefits of learning. His experiments demonstrate that flies have the genetic potential to become significantly smarter in the wild. But only under his lab conditions does evolution actually move in that direction. In nature, any improvement in learning would cost too much. Dr. Kawecki also says it is worth investigating whether humans also pay hidden costs for extreme learning. “We could speculate that some diseases are a byproduct of intelligence.” he said. The benefits of learning must have been enormous for evolution to have overcome those costs, Dr. Kawecki argues.1.According to the text, being smart can be bad for animal’s health because(  ).2.Which of the following is NOT TRUE according to the text?3.Bacteria and microbe are used in Paragraph 2 as examples to show (  ).  4.The sentence "We could speculate that some diseases are a byproduct of intelligence" Dr.Kawecki argues in the last paragraph implies that(  ).

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Mental and physical health professionals may consider referring clients and patients to a music therapist for a number of reasons. It seems a particularly good choice for the social worker who is coordinating a client’s case. Music therapists use music to establish a relationship with the patient and to improve the patient’s health, using highly structured musical interactions. Patients and therapists may sing, play instruments, and compose music, dance, or simply listen to music, dance, or simply listen to music.The course of training for music therapists is comprehensive. In addition to their formal musical and therapy training, music therapists are taught to discern what kinds of interventions will be most beneficial for each individual patient. Since each patient is different and has different goals, the music therapist must be able to understand the Patient’s situation and choose the music and activities that will do the most toward helping the patient achieve his or her goals. The referring social worker can help this process by clearly articulating each client's history.Although patients may develop their musical skills, that is not the main goal of music therapy. Any client who needs particular work on communication or on academic, —emotional and social skills, and who is not responding to traditional therapy, is an excellent candidate for music therapy.1.Which of the following best organizes the main topics addressed in this passage?2.Which of the following would be the most appropriate title for this passage?3.According to information presented in the passage, music therapy can be prescribed for social work clients who(  ).4.Which of the following inferences can be drawn from the passage?

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