1、北京师范大学考博英语模拟试卷 3及答案与解析 一、 Reading Comprehension 0 Birds evolved during the great reptilian radiation of the Mesozoic era. Amniotic eggs and scales on the legs are just two of the reptilian features we see in birds. But modern birds look quite different from modern reptiles because of their feathers
2、and other distinctive flight equipment. Characteristics of Birds Almost every part of a typical birds anatomy is modified in some way that enhances flight. The bones have an internal structure that is honeycombed, making them strong but light. The skeleton of a frigate bird, for instance, has a wing
3、span of more than 2 meters but weighs only about 113 grams. Another adaptation reducing the weight of birds is the absence of some organs. Females, for instance, have only one ovary. Also, modern birds are toothless, an adaptation that trims the weight of the head. Food is not chewed in the mouth bu
4、t ground in the gizzard, a digestive organ near the stomach.(Crocodiles also have gizzards, as did some dinosaurs.)The birds beak, made of keratin, has proven to be very adaptable during avian evolution, taking on a great variety of shapes suitable for different diets. Flying requires a great expend
5、iture of energy from an active metabolism. Birds are endothermic: they use their own metabolic heat to maintain a warm, constant body temperature. Feathers and, in some species, layers of fat provide insulation that enables birds to retain their metabolically generated heat. An efficient respiratory
6、 system and a circulatory system with a four-chambered heart keep tissues well supplied with oxygen and nutrients, supporting a high rate of heat and reduce the density of the body metabolism. The lungs have tiny tubes leading to and from elastic air sacs that help dissipate. For safe flight, senses
7、, especially vision, must be acute. Birds have excellent eyes, perhaps the best of all the vertebrates. The visual areas of the brains are well developed, as are the motor areas: flight also requires excellent coordination. With brains proportionately larger than those of reptiles and amphibians, bi
8、rds generally display very complex behavior. Avian behavior is particularly intricate during breeding season, when birds engage in elaborate rituals of courtship. Because eggs are shelled when laid, fertilization must be internal. Copulation involves contact between the mates vents, the openings to
9、their cloacas. After eggs are laid, the avian embryo must be kept warm through brooding by the mother, father, or both, depending on the species. A birds most obvious adaptation for flight is its wings. Bird wings are airfoils that illustrate the same principles of aerodynamics as the wings of an ai
10、rplane. Providing power for flight, birds flap their wings by contractions of large pectoral(breast)muscles anchored to a keel on the sternum(breast-bone). Some birds, such as eagles and hawks, have wings adapted for soaring on air currents and flap their wings only occasionally, other birds, includ
11、ing hummingbirds, must flap continuously to stay aloft. In either case, it is the shape and arrangement of the feathers that form the wings into an airfoil. The fastest birds are the appropriately named swifts, which can fly 170 km/hr. In being both extremely light and strong, feathers are among the
12、 most remarkable of vertebrate adaptations. Feathers are made of keratin, the same protein that forms our hair and fingernails and the scales of reptiles. Feathers may have functioned first as insulation during the evolution of endotherm, only later being so-opted as flight equipment. Analyses of fo
13、ssilized skeletons support the hypothesis that the closest reptilian relatives of birds were the theropods, a group of relatively small, bipedal carnivorous dinosaurs. Most researchers agree that the ancestor of birds was a feathered theropod. However, some scientists place the origin of birds much
14、earlier, from an ancestor common to both birds and dinosaur. The intense current interest in the origin of birds will undoubtedly bring us closer to understanding how these masters of the sky evolved from non-flying reptiles 1 According to paragraph 2, how did birds adapt to efficient flight? （ A） T
15、hey developed a skeleton with fewer bones. （ B） Their organs became smaller overtime. （ C） Most of their weight was distributed in their heads. （ D） Teeth were replaced by a beak made of keratin. 2 The word “modified“ in the passage is closest in meaning to_. （ A） made different （ B） made better （ C
16、） made smaller （ D） made modern 3 The word “ their“ in the passage refers to_. （ A） feathers （ B） species （ C） layers （ D） birds 4 According to paragraph 6, which of the following is true about the wings of birds? （ A） All birds flap their wings constantly by using breast muscles. （ B） Eagles and ha
17、wks have wings that propel them at 170 km/hr. （ C） The airfoils of birds function like the wings on airplanes. （ D） Wings are attached to airfoils in the birds skeletal structure. 5 According to the passage, which characteristic do birds share with reptiles? （ A） They defend themselves with claws. （
18、 B） They reproduce by laying eggs. （ C） They have a similar skeletal structure. （ D） They utilize a two-chambered heart. 6 Which of the sentences below best expresses the information in the highlighted statement in the passage? （ A） Very early birds appeared after the dinosaurs. （ B） Birds and dinos
19、aurs may share the same ancestor. （ C） Birds and dinosaurs were probably very common. （ D） The origin of birds and dinosaurs is very early. 7 All of the following are mentioned as adaptations to the birds anatomy to accommodate flight EXCEPT_. （ A） a covering of feathers （ B） relatively large brains
20、 （ C） very sharp eyes （ D） small legs and feet 7 When one animal attacks another, it engages in the most obvious example of aggressive behavior. Psychologists have adopted several approaches to understanding aggressive behavior in people. The Biological Approach. Numerous biological structures and c
21、hemicals appear to be involved in aggression. One is the hypothalamus, a region of the brain. In response to certain stimuli, many animals show instinctive aggressive reactions. The hypothalamus appears to be involved in this inborn reaction pattern; electrical stimulation of part of the hypothalamu
22、s triggers stereotypical aggressive behaviors in many animals. In people, however, whose brains are more complex, other brain structures apparently moderate possible instincts. An offshoot of the biological approach called sociobiology suggests that aggression is natural and even desirable for peopl
23、e. Sociobiology views much social behavior, including aggressive behavior, as genetically determined. Consider Darwins theory of evolution. Darwin held that many more individuals are produced than can find food and survive into adulthood. A struggle for survival follows. Those individuals who posses
24、s characteristics that provide them with an advantage in the struggle for existence are more likely to survive and contribute their genes to the next generation. In many species, such characteristics include aggressiveness. Because aggressive individuals are more likely to survive and reproduce, wha
25、tever genes are linked to aggressive behavior are more likely to be transmitted to subsequent generations. The sociobiology view has been attacked on numerous grounds. One is that peoples capacity to outwit other species, not their aggressiveness, appears to be the dominant factor in human survival.
26、 Another is that there is too much variation among people to believe that they are dominated by, or at the mercy of, aggressive impulses. The Psychodynamic Approach. Theorists adopting the psychodynamic approach hold that inner conflicts are crucial for understanding human behavior, including aggres
27、sion. Sigmund Freud, for example, believed that aggressive impulses are inevitable reactions to the frustrations of daily life. Children normally desire to vent aggressive impulses on other people, including their parents, because even the most attentive parents cannot gratify all of their demands i
28、mmediately. Yet children, also fearing their parents punishment and the loss of parental love, come to repress most aggressive impulses. The Freudian perspective, in a sense: sees us as “steam engines. “ By holding in rather than venting “steam,“ we set the stage for future explosions. Pent-up aggre
29、ssive impulses demand outlets. They may be expressed toward parents in indirect ways such as destroying furniture, or they may be expressed toward strangers later in life. According to psychodynamic theory, the best ways to prevent harmful aggression may be to encourage less harmful aggression. In t
30、he steam-engine analogy, verbal aggression may vent some of the aggressive steam. So might cheering on ones favorite sports team. Psychoanalysts, therapists adopting a psychodynamic approach, refer to the venting of aggressive impulses as “catharsis.“ Catharsis is theorized to be a safety valve. But
31、 research findings on the usefulness of catharsis are mixed. Some studies suggest that catharsis leads to reductions in tension and a lowered likelihood of future aggression. Other studies, however, suggest that letting some steam escape actually encourages more aggression later on. The Cognitive Ap
32、proach. Cognitive psychologists assert that our behavior is influenced by our values, by the ways in which we interpret our situations and by choice. For example, people who believe that aggression is necessary and justified-as during wartime are likely to act aggressively, whereas people who believ
33、e that a particular war or act of aggression is unjust, or who think that aggression is never justified, are less likely to behave aggressively. One cognitive theory suggests that aggravating and painful events trigger unpleasant feelings. These feelings, in turn, can lead to aggressive action, but
34、not automatically. Cognitive factors intervene. People decide whether they will act aggressively or not on the basis of factors such as their experiences with aggression and their interpretation of other peoples motives. Supporting evidence comes from research showing that aggressive people often di
35、stort other peoples motives. For example, they assume that other people mean them harm when they do not. 8 According to paragraph 2, what evidence indicates that aggression in animals is related to the hypothalamus? （ A） Some aggressive animal species have a highly developed hypothalamus. （ B） elect
36、rical stimulation of the hypothalamus results in aggression in animals. （ C） Animals behaving aggressively show increased activity in the hypothalamus. （ D） Animals who lack a hypothalamus display few aggressive tendencies. 9 According to Darwins theory of evolution, members of a species are forced
37、to struggle for survival because_. （ A） not all individuals are skilled in finding food （ B） individuals try to defend their young against attackers （ C） many more individuals are born than can survive until the age of reproduction （ D） individuals with certain genes are more likely to reach adultho
38、od 10 According to paragraph 5, Freud believed that children experience conflict between a desire to vent aggression on their parents and_. （ A） a frustration that their parents do not give them everything they want （ B） a fear that their parents will punish them and stop loving them （ C） a desire t
39、o take care of their parents （ D） a desire to vent aggression on other family members 11 Freud describes people as steam engines in order to make the point that people_. （ A） deliberately build up their aggression to make themselves stronger （ B） usually release aggression in explosive ways （ C） mus
40、t vent their aggression to prevent it from building up （ D） typically lose their aggression if they do not express it 12 Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? （ A） People who believe that they are fighting a just war act agg
41、ressively while those who believe that they are fighting an unjust war do not. （ B） People who believe that aggression is necessary and justified are more likely to act aggressively than those who believe differently. （ C） People who normally do not believe that aggression is necessary and justified
42、 may act aggressively during wartime. （ D） People who believe that aggression is necessary and justified do not necessarily act aggressively during wartime. 13 According to the cognitive approach described in paragraphs 7 and 8, all of the following may influence the decision whether to act aggressi
43、vely EXCEPT a persons_. （ A） moral values （ B） previous experiences with aggression （ C） instinct to avoid aggression （ D） beliefs about other peoples intentions 14 The word “distort“ in the passage is closest in meaning to_. （ A） mistrust （ B） misinterpret （ C） criticize （ D） resent 14 The car, and
44、 the roads it travels on, will be revolutionized in the twenty first century. The key to tomorrows “smart cars“ will be sensors. “Well see vehicles and roads that see and hear and feel and smell and talk and act,“ predicts Bill Spreitzer, technical director of General Motors Corporations ITS program
45、, which is designing the smart car and road of the future. Approximately 40, 000 people are killed each year in the United States in traffic accidents. Fully half of these fatalities come from drunk drivers, and many others from carelessness. A smart car could eliminate most of theses car accidents.
46、 It can sense if a driver is drunk via electronic sensors that can pick up alcohol vapor in the air, and refuse to start up the engine. The car could also alert the police and provide its precise location if it is stolen. Smart cars have already been built which can monitor ones driving and the driv
47、ing conditions nearby. Small radars hidden in the bumpers can scan for nearby cars. Should you make a serious driving mistake, the computer would sound an immediate warning. At the MIT Medial Lab, a prototype is already being built which will determine how sleepy you are as you drive, which is espec
48、ially important for long-distance truck drivers. The monotonous, almost hypnotic process of staring at the center divider for long hours is a grossly underestimated, life-threatening hazard. To eliminate this, a tiny camera hidden in the dashboard can be trained on a drivers face and eyes. If the dr
49、ivers eyelids close for a certain length of time and his or her driving becomes erratic, a computer in the dashboard could alert the driver. Two of the most frustrating things about driving a car are getting lost, and getting stuck in traffic. While the computer revolution is unlikely to cure theses problems, it will have a positive impact. Sensors in your car tuned to radio signals from orbiting satellites can locate your car precisely at any moment and warn of traffic jams. We already have twenty-four Navstar satellites orb
