Transgenic animals：转基因动物
Transgenic animals：转基因动物
相关考题：
As research techniques become more______(advance)，the number of animals used in experiments may decrease，but stopping testing on animals altogether is a long way away.
If cloned animals could be used as organ donors, ().A、people don’t have to worry about cloning twins for transplantsB、raising animals such as pigs can help solve the problemC、the human body attacks and destroys tissue from other speciesD、it may be more efficient to produce such animals by cloning than by cur
( ) dogs are clever animals, but they are not ( ) cleverest of all animals. A、The/ theB、The/ aC、…/ ...D、.../ the
Modern zoos are very different from zoos that were built fifty years ago.At that time, zoos were places (1) people could go to see animals from many parts of the world.They animals lived in cages that were made (2) Concrete with iron bars, cages that were easy to keep clean.Unfortunately for the animals, the cages were small and impossible to hide in.the zoos environment was anything (3) natural.Al though the zoo keepers took good care of the animals and fed them well, many of the animals did not thrive: they behaved in strange ways, and they often became illIn modern zoos, people can see animals in more natural habitats.The animals are(4)more freedom in large areas so that they can live more comfortably as they would in nature Even the appearance of zoos has changed, trees and grass grow in the cages, and streams of water flow (5) the areas that animals live in.(完型填空)A.OfB.ButC.WhereD.OverE.Given
It was long supposed ____ the main difference between animals and plants was that animals could move about.A: whichB: thisC: thatD: because
To protect wild animals is our duty．（改为同义句）__________ our duty__________ __________ wild animals．
单选题ADead animals found in dustbins.BSmall animals stolen from houses.CFood given to them by people.DFood that hunted by themselves.
单选题Animals, which are nevertheless displaying some extremely different physiological and behavioral traits, are genetically similar.AAnimals, which are nevertheless displaying some extremely different physiological and behavioral traits, are genetically similar.BThough genetically similar, animals, nevertheless, display some extremely different physiological and behavioral traits.CSome animals that are genetically similar nevertheless display extremely different physiological and behavioral traits.DSome animals display extremely different physiological and behavioral traits, they are genetically similar, nevertheless.ESome animals display extremely different physiological and behavioral traits and are genetically similar.
问答题Practice 2 Transgenic plants and animals result from genetic engineering experiments in which genetic material is moved from one organism to another, so that the latter will exhibit a characteristic. Business corporations, scientists, and farmers hope that transgenic techniques will allow more cost-effective and precise plants and animals with desirable characteristics that are not available using up to date breeding technology. Transgenic techniques allow genetic material to be transferred between completely unrelated organisms. In order for a transgenic technique to work, the genetic engineer must first construct a transgene, which is the gene to be introduced plus a control sequence. When making a transgene, scientists usually substitute the original promoter sequence with one that will be active in the correct tissues of the recipient plant or animal. The creation of transgenic animals is one of the most dramatic advances derived from recombinant DNA technology. A transgenic animal results from insertion of a foreign gene into an embryo. The foreign gene becomes a permanent part of the host animals’ genetic material. As the embryo develops, the foreign gene may be present in many cells of the body, including the germ cells of the testis or the ovary. If the transgenic animal is fertile, the inserted foreign gene (transgene) will be inherited by future progeny. Thus, a transgenic animal, once created, can persist into future generations. Transgenic animals are different from animals in which foreign cells or foreign organs have been engrafted. The progeny of engrafted animals do not inherit the experimental change. The progeny of transgenic animals do. The techniques for creating a transgenic animal include the following: 1) picking a foreign gene, 2) placing the foreign gene in a suitable form called a “construct” which guides the insertion of the foreign gene into the animal genome and encourages its expression, and 3) injecting the construct into a single fertilized egg or at the very early embryo stage of the host animal. Much genetic engineering goes into the choice of a foreign gene and building a construct. The construct must have promoters to turn on foreign gene expression at its new site within the host animal genome. By choosing a particular promoter and splicing it in front of the foreign gene, we can encourage expression of our transgene within a specific tissue. One of the most important applications of transgenic animals is the development of new animal models of human disease. Transgenic animals can serve as models for many malignant tumors. Mice have been the most frequent hosts for transgenic modification, other domestic animals have also been used. One idea has been to create transgenic cows which secrete important pharmaceutical substances in their milk. Other attempts are being made to express human interferon in the milk of sheep. A transgenic crop plant contains a gene or genes which have been artificially inserted instead of the plant acquiring them through pollination. The inserted gene sequence (known as the transgene) may come from another unrelated plant, or from a completely different species: transgenic BT corn, for example, which produces its own insecticide, containing a gene from a bacterium. Plants containing transgenes are often called genetically modified or GM crops although in reality all crops have been genetically modified from their original wild state by domestication, selection and controlled breeding over long periods of time.
单选题AThey are harmful animals.BThey are strange animals.CThey are attractive animals.DThey are friendly animals.
单选题利用PubMed文献数据查找论文“Transgenic plants of Petunia hybrida harboring the CYP2E1 gene efficiently remove benzene and toluene pollutants and improve resistance to formaldehyde”的第一作者是（）。AXiangTBBaoLCLiPDZhangD