AccordingtoStevenYoung,ifscientistsgetthedatathat________,theywouldpetitionforfasttrackstatus.
Because the virus changes its shape.
暂无解析
Without regular supplies of some hormones our capacity to behave would be seriously impaired; without others we would soon die. Tiny amounts of some hormones can modify moods and actions, our inclination to eat or drink, our aggressiveness or submissiveness, and our reproductive and parental behavior. And hormones do more than influence adult behavior; early in life they help to determine the development of bodily form and may even determine an individual’s behavioral capacities. Later in life the changing outputs of some endocrine glands and the body’s changing sensitivity to some hormones are essential aspects of the phenomena of aging.
Communication within the body and the consequent integration of behavior were considered the exclusive province of the nervous system up to the beginning of the present century. The emergence of endocrinology as a separate discipline can probably be traced to the experiments of Bayliss and Starling on the hormone secretion. This substance is secreted from cells in the intestinal walls when food enters the stomach; it travels through the bloodstream and stimulates the pancreas to liberate pancreatic juice, which aids in digestion. By showing that special cells secret chemical agents that are conveyed by the bloodstream and regulate distant target organs or tissues. Bayliss and starling demonstrated that chemical integration could occur without participation of the nervous system.
The term “hormone” was first used with reference to secretion. Starling derived the term from the Greek hormone, meaning “to excite or set in motion. The term “endocrine” was introduced shortly thereafter “Endocrine” is used to refer to glands that secret products into the bloodstream. The term “endocrine” contrasts with “exocrine”, which is applied to glands that secret their products though ducts to the site of action. Examples of exocrine glands are the tear glands, the sweat glands, and the pancreas, which secrets pancreatic juice through a duct into the intestine. Exocrine glands are also called duct glands, while endocrine glands are called ductless.
1.What is the author’s main purpose in the passage?
A.To explain the specific functions of various hormones.
B.To provide general information about hormones.
C.To explain how the term “hormone” evolved.
D.To report on experiments in endocrinology.
2.The passage supports which of the following conclusions?
A.The human body requires large amounts of most hormones.
B.Synthetic hormones can replace a person’s natural supply of hormones if necessary.
C.The quantity of hormones produced and their effects on the body are related to a person’s age.
D.The short child of tall parents very likely had a hormone deficiency early in life.
3.It can be inferred from the passage that before the Bayliss and Starling experiments, most people believed that chemical integration occurred only___.
A.during sleep.
B.in the endocrine glands.
C.under control of the nervous system.
D.during strenuous exercise.
4.The word “liberate” could best be replaced by which of the following?
A.Emancipate B.Discharge C.Surrender D.Save
5.According to the passage another term for exocrine glands is___.
A.duct glands
B.endocrine glands
C.ductless glands
D.intestinal glands.
Lifeistooshort________________(不可每天将时间浪费在看电视上).
We can begin our discussion of “population as global issue” with what most persons mean when they discuss “the population problem”: too many people on earth and a too rapid increase in the number added each year. The facts are not in dispute, It was quite right to employ the analogy that likened demographic growth to “a long, thin powder fuse that burns steadily and haltingly until it finally reaches the charge and explodes.”
To understand the current situation, which is characterized by rapid increases in population, it is necessary to understand the history of population trends. Rapid growth is a comparatively recent phenomenon. Looking back at the 8,000 years of demographic history, we find that populations have been virtually stable or growing very slightly for most of human history. For most of our ancestors, life was hard, often nasty, and very short. There was high fertility in most places, but this was usually balanced by high mortality. For most of human history, it was seldom the case that one in ten persons would live past forty, while infancy and childhood were especially risky periods. Often, societies were in clear danger of extinction because death rates could exceed their birthrates. Thus, the population problem throughout most of history was how to prevent extinction of the human race.
This pattern is important to notice. Not only does it put the current problems of demographic growth into a historical perspective, but it suggests that the cause of rapid increase in population in recent years is not a sudden enthusiasm for more children, but an improvement in the conditions that traditionally have caused high mortality.
Demographic history can be divided into two major periods: a time of long, slow growth which extended from about 8,000 BC.till approximately AD. 1650. In the first period of some 9600 years, the population increased from some 8 million to 500 million in 1650. Between 1650 and the present, the population has increased from 500 million to more than 4 billion. And it is estimated that by the year 2000 there will be 6.2 billion people throughout the world. One way to appreciate this dramatic difference in such abstract numbers is to reduce the time frame to something that is more manageable. Between 8000BC and 1650, an average of only 50,000 persons was being added annually to the world’s population each year. At present, this number is added every six hours. The increase is about 80,000,000 persons annually.
1.Which of the following demographic growth pattern is most suitable for the long thin powder fuse analogy?
A.A virtually stable or slightly decreasing period and then a sudden explosion of population.
B.A slow growth for a long time and then a period of rapid, dramatic increase.
C.Too many people on earth and a few rapid increase in the number added each year.
D.A long period when death rates exceeds birthrates and then a short period with higher fertility and lower mortality.
2.During the first period of demographic history, societies were often in danger of extinction because___.
A.only one in ten persons could live past 40.
B.there was higher mortality than fertility in most places.
C.it was too dangerous to have babies due to the poor conditions.
D.our ancestors had little enthusiasm for more children.
3.Which statement is true about population increase?
A.There might be an increase of 2.2 billion persons from now to the year 2000.
B.About 50,000 babies are born every six hours at present.
C.Between 8000 BC and the present, the population increase is about 80,000,000 persons each year.
D.The population increased faster between 8000BC and 1650 than between 1650 and the present.
4.The author of the passage intends to___.
A.warn people against the population explosion in the near future.
B.compare the demographic growth pattern in the past with that after 1650.
C.find out the cause for rapid increase in population in recent years.
D.present us a clear and complete picture of the demographic growth.
5.The word “demographic” in the first paragraph means___.
A.statistics of human.
B.surroundings study.
C.accumulation of human.
D.development of human.
翻译训练:地域特色文明
文明是多彩的,人类文明因多样才有交流互鉴的价值。文明是平等的,人类文明因平等才有交流互鉴的前提。文明是包容的,人类文明因包容才有交流互鉴的动力。
当今世界,人类生活在不同文化、种族、肤色、宗教和不同社会制度所组成的世界里,各国人民形成了你中有我、我中有你的命运共同体。应该推动不同文明相互尊重、和谐共处,让文明交流互鉴成为增进各国人民友谊的桥梁、推动人类社会进步的动力、维护世界和平的纽带。应该从不同文明中寻求智慧、汲取营养,为人们提供精神支撑和心灵慰藉,携手解决人类共同面临的各种挑战。
Whatdoesthefutureholdfortheproblemofhousing?Agooddealdepends,ofcourse,onthemeaningof“future”.Ifoneisthinkingintermsofsciencefictionandthespaceage,itisatleastpossibletoassumethatmanwillhavesolvedsuchtrivialandearthlyproblemsashousing.Writersofsciencefiction,fromH.G.Wellsonwards,havehadlittletosayonthesubject.Theyhaveconveyedthesuggestionthatmenwillliveingreatcomfort,witheveryconceivableapparatustomakelifesmooth,healthyandeasy,ifnothappy.Buttheyhavenotsaidwhathishousewillbemadeof.Perhapssomenewbuildingmaterial,asyetunimagined,willhavebeendiscoveredorinventedatleast.Onemaybecertainthatbricksandmortar(泥灰,灰浆)willlonghavegoneoutoffashion.
Buttheproblemsofthenextgenerationortwocanmorereadilybeimagined.Scientistshavealreadypointedoutthatunlesssomethingisdoneeithertorestricttheworld’srapidgrowthinpopulationortodiscoveranddevelopnewsourcesoffood(orboth),millionsofpeoplewillbedyingofstarvationoratthebestsufferingfromunderfeedingbeforethiscenturyisout.Butnobodyhasyetworkedoutanyplanforhousingthesegrowingpopulations.Admittedlytheworstsituationswilloccurinthehottestpartsoftheworld,wherehousingcanbelightstructureorinbackwardareaswherestandardsaretraditionallylow.Buteventheminimumshelterrequiresmaterialsofsomekindandintheteeming,bulgingtownsthelow-standard“housing”offlattenedpetrolcansanddirtycanvasisfarmorewastefulofgroundspacethancanbetolerated.
Sincethewar,HongKonghassufferedthekindofcrisiswhichislikelytoariseinmanyotherplacesduringthenextgeneration.Literallymillionsofrefugeesarrivedtoswellthealreadygrowingpopulationandemergencystepshadtobetakenrapidlytopreventsqualor(肮脏)anddiseaseandthespreadcrime.Thecityistacklingthesituationenergeticallyandenormousblocksoftenements(贫民住宅)arerisingatanastonishingaped.ButHongKongisonlyonesmallpartofwhatwillcertainlybecomeavastproblemandnotmerelyahousingproblem,becausewhenpopulationgrowsatthisratethereareaccompanyingproblemsofeducation,transport,hospitalservices,drainage,watersupplyandsoon.NoteveryareamaygivethesameresourcesasHongKongtodrawuponandthesearchforquickerandcheapermethodsofconstructionmustnevercease.
1.Whatistheauthor’sopinionofhousingproblemsinthefirstparagraph?
A.Theymaybecompletelysolvedatsometimeinthefuture.
B.Theyareunimportantandeasilydealtwith.
C.Theywillnotbesolveduntilanewbuildingmaterialhasbeendiscovered.
D.Theyhavebeendealtwithinspecificdetailinbooksdescribingthefuture.
2.Thewriterissurethatinthedistantfuture___.
A.bricksandmortarwillbereplacedbysomeotherbuildingmaterial.
B.anewbuildingmaterialwillhavebeeninvented.
C.bricksandmortarwillnotbeusedbypeoplewhowanttheirhousetobefashionable.
D.anewwayofusingbricksandmortarwillhavebeendiscovered.
3.Thewriterbelievesthatthebiggestproblemlikelytoconfronttheworldbeforetheendofthecentury___.
A.isdifficulttoforesee.
B.willbehowtofeedtheevergrowingpopulation.
C.willbehowtoprovideenoughhousesinthehottestpartsoftheworld.
D.isthequestionoffindingenoughgroundspace.
4.Whenthewritersaysthattheworstsituationswilloccurinthehottestpartsoftheworldorinbackwardareas,heisreferringtothefactthatintheseparts___.
A.standardsofbuildingarelow.
B.onlyminimumshelterwillbepossible.
C.thereisnotenoughgroundspace.
D.thepopulationgrowthwillbethegreatest.
5.WhichofthefollowingsentencesbestsummarizesParagraph3?
A.HongKonghasfacedaseriouscrisiscausedbymillionsofrefugees.
B.HongKonghassuccessfullydealtwiththeemergencycausedbymillionsofrefugees.
C.HongKong’scrisiswasnotonlyamatterofhousingbutincludedanumberofotherproblemsofpopulationgrowth.
D.ManypartsoftheworldmayhavetofacethekindofproblemsencounteredbyHongKongandmayfinditmuchhardertodealwiththem.