单选题DNA聚合酶催化的反应( )。

单选题白眼雌蝇与红眼雄蝇杂交，后代出现白眼雌蝇的概率是( )。

单选题 遗传漂变在所有的群体中都能出现，不过（ ）。 A、群体越大，漂变就越小 B、群体越大，漂变就越大 C、群体很小时，漂变可以忽略不计 D、群体很大时，漂变的效果明显

单选题基于16SrRNA的系统发生将生物界分为( )。

单选题序列(IS)编码______。

单选题等位基因是______。

单选题有关PCR的描述下列哪项不正确?( )

单选题在烟草花叶病毒感染实验中，用A型变种的RNA与B型变种的蛋白质重建杂合病毒颗粒，再感染烟草，结果得到______子代。

单选题一个AB血型人的母亲不可能是______。

单选题睾丸女性化是( )。

单选题 断裂基因中的编码序列，称为（ ）。 A、内含子　　B、外显子　　C、转座子　　D、操纵子

单选题假设某种二倍体植物A的细胞质在遗传上不同于植物B，为了研究核一质关系，想获得一种植株，这种植株具有A的细胞质，而细胞核主要是B的基因组，应该怎么做?

单选题The history of responses to the work of the artist Sandro Botticelli (1444 ～ 1510) suggests that widespread appreciation by critics is a relatively recent phenomenon. Writing in 1550, Vasari expressed an unease with Botticelli's work, admitting that the artist fitted awkwardly into his evolutionary scheme of the history of art. Over the next two centuries, academic art historians defamed Botticelli in favor of his fellows Florentine, Michelangelo. Even when anti-academic art historians of the early nineteenth century rejected many of the standards of evaluation adopted by their predecessors, Botticelli's work remained outside of accepted taste, pleasing neither amateur observers nor connoisseurs. (Many of his best paintings, however, remained hidden away in obscure churches and private homes. ) The primary reason for Botticelli's unpopularity is not difficult to understand: most observers, up until the midnineteenth century, did not consider him to be noteworthy, because his work, for the most part, did not seem to these observers to exhibit the traditional characteristics of fifteenth-century Florentine art. For example, Botticelli rarely employed the technique of strict perspective and, unlike Michelangelo, never used chiaroscuro. Another reason for Botticelli's unpopularity may have been that his attitude toward the style of classical art was very different from that of his contemporaries. Although he was thoroughly exposed to classical art, he showed little interest in borrowing from the classical style. Indeed, it is paradoxical that a painter of large-scale classical subjects adopted a style that was only slightly similar to that of classical art. In any case, when viewers began to examine more closely the relationship of Botticelli's work to the tradition of fifteenth-century Florentine art, his 'reputation began to grow. Analyses and assessments of Botticelli made between 1850 and 1870 by the artists of the Pre Raphaelite movement, as well as by the writer Pater (although he, unfortunately, based his assessment on an incorrect analysis of Botticelli's personality), inspired a new appreciation of Botticelli throughout the English-speaking world. Yet Botticelli's work, especially the Sistine frescoes, did not generate worldwide attention until it was finally subjected to a comprehensive and scrupulous analysis by Home in 1908. Home rightly demonstrated that the frescoes shared important features with paintings by other fifteenth-century Florentines features such as skillful representation of anatomical proportions, and of the human figure in motion. However, Home argued that Botticelli did not treat these qualities as ends in themselves--rather, that he emphasized clear depletion of a story, a unique achievement and one that made the traditional Florentine qualities less central. Because of Home's emphasis crucial to any study of art, the twentieth century has come to appreciate Bottieelli's achievements.

单选题外耳道多毛症是一种遗传病，父亲是患者，则儿子全是患者，女儿全正常。此遗传病基因是( )。

单选题When an invention is made, the inventor has three possible (1) of action open to him: he can give the invention to the world by publishing it, keep the idea (2) , or patent it. A (3) patent is the result of a bargain (4) between an inventor and the state, hut the inventor gets a limited period of monopoly and publishes full details of his invention to the public after that period (5) . Only in the most exceptional circumstances (6) the lifespan of a patent (7) to alter this normal process of events. The longest extension ever (8) was to Georges Valensi; his 1939 patent for color TV receiver circuit was extended until 1971 because for most of the patent's normal life there was no color TV to (9) and thus no hope for reward for the invention. Because a patent remains permanently (10) after it has terminated, the shelves of the library attached to the (11) office contain details of literally millions of ideas that are free for anyone to use and, if (12) than half a century, sometimes even repatent. Indeed, patent experts often advise anyone (13) to avoid the high cost of conducting a search through (14) patents that the one sure way of violation of any other inventor's right is to plagiarize a dead patent. Likewise, because publication of an idea in any other form (15) invalidates further patents on that idea, it is traditionally (16) to take ideas from other areas of print. Much modern technological advance is (17) on these presumptions of legal security. Anyone closely (8) in patents and inventions soon learns that most "new" ideas are, in fact, as old as the hills. It is theft reduction to commercial practice, either through necessity or dedication, or through the availability of new technology, (19) makes news and money. The basic patent for the theory for magnetic recording dates back to 1886. Many of the original ideas behind television originate (20) the late 19th and early 20th century. Even the Volkswagen rear engine ear was anticipated by a 1904 patent for a cart with the horse at the rear.

单选题两对基因杂合体F 1 (AaBb)自交后代重组型等于亲组型的遗传是( )。

单选题 符合系数等于1，说明（ ）。 A、没有干扰　　B、发生了完全干扰　　C、干扰很大　　D、干扰较小

单选题"I was just like you--I' thought I was invincible," says Adam Blomberg, standing before 400 students in a darkened auditorium at Miami's Coral Reef Senior High School. A photo of a bloodied and unconscious teenager, a breathing tube protruding from his mouth, flashes on the wall. "That was me," he says. There's a collective gasp before the room grows silent and Blomberg,31, an anesthesiologist who trained at Brigham and Women's Hospital in Boston, begins the story of what happened one night in February 1995. He created a presentation illustrating the dangers of behaving irresponsibly in a car, from not buckling up to speeding to driving under the influence of alcohol and drugs. He tracked down photos of teen crash victims from the center's archives, then incorporated statistics and his own experience. He spoke the first time to a local Boy Scout troop and was soon giving his talk, "A Survivor's Story," at high schools around the state. The Blomberg family had reason to celebrate. Adam had fully recovered and was on his way to fulfilling his lifelong dream of becoming a doctor. But in January 2000, Blomberg's 22-year-old step-brother, Michael, was killed in a crash while driving to his Atlanta home late one night. He wasn't wearing a seat belt. After the accident, Blomberg stopped telling his story to crowds, racked with guilt over his inability to reach Michael. If Blomberg had failed his own brother, he reasoned, how could he possibly make a difference to a roomful of strangers? Requests from schools continued to roll in, but he turned down every one. Then Blomberg got a call from a high school counselor. As he started into his standard excuse-lack of time—he looked across the room at a stack of thank-you notes from students who had heard him speak. He realized that kids needed to hear what he had to say. He agreed to visit the school and began contacting others on the waiting list for his talks. Blomberg leaves the school hoping he has changed someone's behavior. He recalls a letter he received from a student who heard him speak and got into a crash later that same day but was unharmed. " She told me she was wearing her seat belt because of me." Letters like this reinforce his belief that he survived the accident for a reason. "There are a lot of physicians in the world, and we all save lives," he says. "I have a special opportunity to save lives not just as a doctor but also as a human being./

单选题下列性别畸形个体的体内相对不含雄性激素的是( )。

单选题以下哪种情况不属于同源重组?( )