Human biomarkers in breath by photoacoustic

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安徽省合肥市庐阳区第六中学2025届高三下学期第五次调研考试英语试题含解析

安徽省合肥市庐阳区第六中学2025届高三下学期第五次调研考试英语试题注意事项1．考生要认真填写考场号和座位序号。

2．试题所有答案必须填涂或书写在答题卡上，在试卷上作答无效。

第一部分必须用2B 铅笔作答；第二部分必须用黑色字迹的签字笔作答。

3．考试结束后，考生须将试卷和答题卡放在桌面上，待监考员收回。

第一部分（共20小题，每小题1.5分，满分30分）1．In front of the whole audience, Premiere Li made his promise ______ the government would try its best to solve the problem of poverty in China.A．what B．whichC．whether D．that2．—I know it is really a lot to ask, but can I use your apartment during the summer?— ________. I happen to be out of town. It is all for your taking.A．Behave yourself B．Be my guestC．Have fun D．Take care3．Tom looked at Jenny, with tears _______ his eyes, and shouted out the words _______ in his heart for years. A．filling; having been hidden B．filled; hiddenC．filling; hidden D．filled; hiding4．With the development of science, more new technology ______ to the fields of IT.A．has introduced B．is being introducedC．is introduced D．was introduced5．---The prices of vegetables are going up madly. It’s really too much for us.---But for the situation where many vegetable producing areas _____ constant low temperature, things would not be like this.A．meet with B．have met withC．met with D．had met with6．The teacher came into the classroom _______ by his students.A．following B．to be following C．followed D．having followed.7．—What’s up? You look down. —I have piles of papers ________, but I type so slowly.A．to be typed B．typed C．to type D．being typed8．－The online shopkeeper has made an apology for his rude behavior.－OK. If you’re still not satisfied, you can _______ compensation.A．claim B．affordC．sacrifice D．dismiss9．Anna was in Inner Mongolia for two years, ____ as a volunteer teacher.A．having worked B．working C．worked D．to work10．What a pity! ________joined in the party, I would have met my old friend．A．lf I have B．Had I C．I had D．Have I11．The village evolved into a major e-commerce center, and _____ the past, the villagers owed their success to the reform and opening-up policy.A．reviewed B．reviewingC．to review D．being reviewed12．______ for the fire at Notre Dame de Paris, a church famous for its large collection of art treasures, I would be there for a visit this summer vacation.A．Had it not been B．Should it not beC．Were it not be D．If had it not been13．My wife sometimes _____ something she has long been looking for. That’s why she enjoys window shopping. A．looks up B．looks for C．picks up D．picks out14．Y ou can only be sure of _____ you have at present; you cannot be sure of something _____ you might get in the future.A．that; what B．what; / C．which; that D．/; that15．—Mum, I am worrying about my pet dog while we are away.—Boy, you ________. Our neighbor has offered to help us.A．can’t B．wouldn’t C．needn’t D．mustn’t16．In some countries, people eat with chopsticks, while in ________, knives and forks.A．another B．otherC．others D．the other17．Men must consider eating, drinking, clothing and finding shelter _____ they can pursue entertainment and recreation.A．until B．unlessC．before D．because18．I feel I am as well-behaved and as careful as my deskmate, but _______ I always fall behind?A．how about B．how comeC．what if D．what for19．We offered to pay our half of the cost that was needed to restore the shared doorway but Charles would have of it.A．nothing B．anythingC．none D．any20．We can communicate________people in every part of the world ________the Internet.A．with；with B．with；throughC．through；through D．through；with第二部分阅读理解（满分40分）阅读下列短文，从每题所给的A、B、C、D四个选项中，选出最佳选项。

2023-2024学年江苏省新海高级中学高一上学期英语10月考试英语试题

2023-2024学年江苏省新海高级中学高一上学期英语10月考试英语试题1. In some cases, specific groups may be formed to ________ specific issues.A．put B．press C．address D．make2. When ________ with the size of the whole earth, the biggest ocean does not seem big at all.A．to compare B．comparing C．compare D．compared3. Mary wishes that she ________ law instead of history when she was in college.A．had studied B．studies C．has studied D．studied4. He is very ________ to show up on time, for he is always punctual.A．possible B．probable C．possibly D．likely5. When he finally returned to his hometown, he found it completely ________.A．changing B．to change C．changed D．changes6. —What do you want to do next? We have half an hour until the basketball game.—It’s up to you. ________ you want to do is fine with me.A．No matter what B．However C．Whatever D．Whichever7. I’m moving to the country because the air there is much fresher than ________ in the city.A．ones B．one C．that D．those8. Perhaps they have experienced something similar and do not want you to ________ the same pain.A．break through B．go through C．think through D．see through9. John invited about 40 people to his wedding, most of are family members.A．them B．which C．whom D．that10. There is no point ________ about it, because you always don’t care about anything.A．to ask B．asking C．asked D．asksBelow is a brief description of the process involved in selecting the Nobel Prize laureates (获奖者) in physics.September-Nomination (提名) forms are sent out.The Nobel Committee sends out confidential forms to around 3,000 people-selected professors at universities around the world, Nobel Prize laureates in physics and chemistry, and members of the Royal Swedish Academy of Sciences, among others.February-Deadline for submission.The completed nomination forms must reach the Nobel Committee no later than 31st January of the following year. The Committee screens the nominations and selects the preliminary candidates. About 250-350 names are nominated as several nominators often submit the same name.March-May-Consultation with experts.The Nobel Committee sends the names of the preliminary (初步的) candidates to specially appointed experts for their assessment o f the candidates’ work.Jun-August-Writing of the report.The Nobel Committee puts together the report with recommendations to be submitted to the Academy. The report is signed by all members of the Committee.September-Committee submits recommendations.The Nobel Committee submits its report with recommendations on the final candidates to the members of the Academy. The report is discussed at two meetings of the Physics Class of the Academy.October-Nobel Prize laureates are chosen.In early October, the Academy selects the Nobel Prize laureates in physics through a majority vote. The decision is final and without appeal. The names of the Nobel Laureates are then announced. December-Nobel Prize laureates receive their prize.The Nobel Prize award ceremony takes place on 10 December in Stockholm, where the Nobel Prize laureates receive their Nobel Prize, which consists of a Nobel Prize medal and diploma (证书), and a document confirming the prize amount.11. When should nomination forms be sent back to the Nobel Committee in the following year?A．Later than March. B．Later than April.C．Earlier than February. D．Later than August.12. Where does the Nobel Prize laureates receive their Nobel Prize?A．In Stockholm. B．In New York. C．In Canberra. D．In London.13. The Nobel Prize is NOT made up of_________.A．A medal. B．A diploma. C．A document. D．A souvenir.Jane Austen ever popularLast summer, the UK honored one of its favorite writers, Jane Austen (1775-1817), by making her the face of the new £10 note. In the 200 years since her death, Austen’s fame has increased to global fame.Yet Austen’s works are so very English that it’s rather strange she should be so popular all over the world. Her novels are so of her time that it’s remarkable that she’s still apprecia ted in this verydifferent age. Her most famous works — including Pride and Prejudice the one for which she is most known — are set in the world of the English gentry (上流社会人士) in the early 19th century.Most of her fiction is about young women of that time. Women of the gentry could not work, so their chances of happiness or even basic living depended upon finding a husband. This is a very serious subject, of course, but the joy of Austen’s stories is her ability to make wonderful, but also touching comedy out of something so serious.Take Pride and Prejudice as an example. The main plot of the novel is driven by the love-hate relationship between Elizabeth and Mr Darcy, a wealthy man. At first, they don’t get on. Elizabeth finds Darcy too proud; she feels he thinks he is better than everyone else. She thinks that he looks down upon her family in particular. Darcy, while admiring Elizabeth, believes that she has taken unfairly to him. The pleasure of the novel is reading how these difficulties are overcome and how the comical and unexpected ending is achieved.If we think about this story, it’s obvious why Jane Austen is still popular more than 200 years after her death, and why readers can still have the same feelings with characters from the long dead world of the 19th century English gentry. Although there have been many changes since that time, it’s still the greatest challenge in life for men and women to find the partner of their dreams.14. It can be concluded from Paragraph 2 that the author ________.A．believes Jane Austen’s works are ahead of her timeB．thinks that everyone should read Jane Austen’s worksC．is surprised that Jane Austen’s works are still so popularD．has doubts about Jane Austen’s popularity all over the world15. According to the text, Pride and Prejudice ________.A．has a sad and unexpected endingB．deals with a serious social issue in a lighthearted wayC．centers on poor people’s struggles in the early 19th centuryD．tells readers that everyone can succeed through hard work16. We can learn from the text that Jane Austen remains popular today because ________.A．readers enjoy reading love stories about wealthy peopleB．readers can always find something new from her novelsC．her works deal with problems m any of today’s readers still faceD．readers are attracted by the way people deal with difficulties in the stories17. The text is mainly written to ________.A．introduce the story of Pride and PrejudiceB．explain why Jane Austen is still popular todayC．introduce Jane Austen’s creative writing styleD．tell us why Jane Austen is chosen to be on the new £10 noteAs a child, Paolo Fanciulli was attracted by underwater abandoned ships , particularly the fish and seagrass that lived in them. But in the past decade , his job as a fisherman has grown harder, as trawling ( 用拖网捕鱼) near the coast has been destroying the Mediterranean ecosystem.“The nets are weighed down with heavy chains to be dragged on the sea bottom, so they uproot the seagrass that is key to the Mediterranean ecosystem" he said.While Italian law bans trawling within 5.5km of the coast, it's so profitable that it's not uncommon for boats to carry on illegally at night.In 2006, a desperate Tuscan government dropped concrete blocks into the sea to interrupt the trawlers. Fanciulli said they didn't work as they were too far apart and the nets simply dragged between them. He then began to wonder: what if, instead of dropping concrete blocks into the water, he dropped art? He asked a mine in nearby Carrara to donate two marble (大理石) blocks to make sculptures. They donated 100 instead.Through word of mouth , contributions and online crowdfunding, Fanciulli persuaded artists including Giorgio Butini and Beverly Pepper to carve sculptures from the marble.Then he took them to sea and lowered them in. The underwater sculptures create both a physical brier for nets and a unique underwater museum.The“museum”appears to be having some effects gradually. Although 10 years ago the seagrass was disappearing, it is now growing back. The statues also deserve credit for helping to preserve the fishing industry by protecting the fish resources because the nursery areas of various commercial fish species are below the coast. All kinds of undersea life appears to be returning. Seagrass covers the statues, shellfish has taken up residence, and more dolphins have been seen.Fanciulli hopes to build on the museum's success.“We put in the first statues in 2007 but our goal is to reach 100,”he said, sensing an opportunit y.18. What has made Fanciulli's job grow harder?A．An illegal fishing practice.B．The declining fishing industry.C．The concrete blocks underwater.D．The increasing number of fishermen.19. What does Fancilli mean by“dropped art”in paragraph 3?A．Establishing an art museum.B．Removing the concrete blocks.C．Appealing for artists' donation.D．Laying sculptures under the sea.20. Which of the following can best describe Fanciulli's measure?A．Fruitless. B．Doubtful.C．Conventional. D．Rewarding.21. What's the text mainly about?A．Benefits brought by fine arts.B．Harm trawling does to marine life.C．Efforts by a fisherman to protect sea life.D．Attempts by artists to preserve biodiversity.Human beings are not alone in having invented vaccination, while honeybees got there first and they can run what look like vaccination programmes, which has been confirmed by Gyan Harwood of the University of Illinois, Urbana-Champaign.Queen bees vaccinate their eggs before they are laid. But the question is how the queen receives her antigen supply, for she lives purely on royal jelly, a substance secreted by nurse bees when they are in the life stage of feeding the young. Dr Harwood wondered if the nurses combined the royal jelly they produced with pieces from pathogens they had consumed while eating something brought in from outside.To test this idea, they collected about 150 nurse bees and divided them among six queenless mini hives equipped with the young to look after. They fed the nurses on sugar-water, and for three of the hives they added Paenibacillus larvae, a bacterium causing a disease, to sugar-water.Dr Harwood and Dr Salmela labeled the bacteria with a certain dye, to make them easy to track. And, sure enough, microscope confirmed that Paenibacillus larvae were getting into royal jelly secreted by those bees which had been fed with the sugar-water. Moreover, examination of this royal jelly revealed higher levels of defensive substance, compared with royal jelly from bees that had not been mixed with Paenibacillus larvae. This substance is thought to help bee immune systems fight against bacterial infections.All told, these findings suggest that nurse bees are indeed, via their royal jelly, passing antigens on to the queen, then into eggs. They also mean, because the young receive royal jelly for the first few days after they hatch, the nurses are giving the young the second antigens. Each young bee is therefore being vaccinated twice.22. What puzzled Dr Harwood from paragraph 2?A．What the royal jelly consists of.B．Where nurse bees receive pathogens.C．How the antigen come into the queen bees' bodies.D．Whether honeybees run vaccination earlier than man.23. How did Dr Harwood develop his experiment?A．By dividing bees into different roles.B．By keeping track of the special bacterium.C．By changing the components of royal jelly.D．By observing nurse bees' different behaviors.24. What can we infer according to the results of the experiment?A．Nurse bees are the key to vaccination for bee group.B．The nurse bees pass the antigen only to the queen.C．Bacteria-used royal jelly has fewer defense substances.D．Two vaccinations are given to young bees by caregivers directly.25. Where is the text probably taken from?A．A pet guide. B．A social website.C．An official document. D．A medical magazine.The effects of working while attending school or collegeYouths working while in school or college seems like a tradition in many countries and the trend is growing. A recent study has found that 80% of students in some countries have at least a part time job during their study years.Why do students look for employment? 26 Education costs are high, and college tuitions have grown considerably during the last few years. Moreover, parents also contribute less toward covering the education costs of their children, which means students must earn their own money while studying.Having a job during school or college years affects the stu dents’ personal and academic lives. First of all, employed students have less free time and, as a result, they can’t be around their family or friends as often as they would want. They lack sleep and are more stressed, and they may even develop health problems. Furthermore, student employment also impacts academic performance. A new research shows that students working more than 20 hours a week have lower grades than those who work less or not at all. 27However, the benefits of student employment are also notable. It seems that employed students tend to be more engaged in academic activities than those who do not work, probably because they have developed a higher sense of responsibility.28 Firstly, fresh graduates who already have work experience gained during their study years have better chances of landing a job. Employers usually prefer to hire a graduate with workplace experience, because they needn’t spend too much time and resources to train the new employee. Secondly, studies show that working learners are more likely to move into a managerial position soon after graduating. 29 As they try different jobs during their school years, they are more aware of their job preferences and target field, and thus far less confused than fresh graduates who have never worked.To sum up, because of financial difficulties, many youths look for employment while attending school or college, and this can have positive or negative effects on their lives.30 In this way, employed students can gain noteworthy advantages in terms of career path after they graduate.It was a cold November morning. My alarm clock had just ________ off but I was having trouble getting out of bed.My Dad, who had been my hero growing up, had passed away a few weeks before, leaving me weighed down by________ and depression. Dad loved me. Still, he had been raised ina(n)________way and raised us that way too. I couldn't remember, for example, ever being________ by him after I grew up. Before his________， we talked more, but still________ touched and never hugged. Then, his health began to rapidly ________ and within a few months he left us.That morning, I was too numb ( 麻木的) inside myself to ________ anything. I kept thinking what I would have ________ in exchange for just one last hug from him. Sad and weak,I was unable to gather ________ to get up. When I finally did and ________ out, my son, rushing to meet me, suddenly,________ his arms and gave me a heart-felt hug. Meanwhile, my Dad's ________ rang deep inside me,“Joey，this hug is from me!” Tears w elled up in my eyes." Right then, I realized I couldn't ________ on life.Life can seem very long but in truth it is so ________ that we can never afford to miss a dearest hug!31.A．taken B．gone C．come D．set32.A．anxiety B．surprise C．sadness D．curiosity33.A．single-handed B．open-minded C．cold-blooded D．old-fashioned 34.A．criticized B．loved C．hugged D．cheered35.A．treatment B．return C．retirement D．death36.A．rarely B．instantly C．regularly D．usually37.A．improve B．recover C．restore D．fail38.A．understand B．feel C．see D．say39.A．given B．lost C．bought D．got40.A．attention B．speed C．strength D．support41.A．walked B．cried C．climbed D．slipped42.A．waved B．opened C．crossed D．raised43.A．sound B．comment C．voice D．scream44.A．drop in B．cut down C．miss out D．give up45.A．brief B．precious C．different D．significant46. China’s leaders __________ (强调) the need for increased co-operation between Third World countries in the past decades.(根据汉语提示单词拼写)47. Our plans need to be __________(灵活的，可变通的) enough to cater for the needs of everyone. （根据汉语提示单词拼写）48. It is said that body language _________ (占) 55 per cent of the first impression while what you say just 7 per cent. （根据中文提示填空）49. Raising animals was only ________(次要的) to other forms of farming. (根据汉语提示单词拼写)50. These health care products are __________ at the old people. (根据句意单词拼写)51. In v__________ of his health state, the doctor made a special diet for him. (根据首字母单词拼写)52. Some of my r__________ customers turned up, saw what was going on and left without having a drink. (根据首字母单词拼写)53. He asked several questions __________ (concern) the future of the company. (所给词的适当形式填空)54. Some hospital patients experience high levels of ________ (anxious). （所给词的适当形式填空）55. __________ (base) on a true story, the book tells about a boy named Auggie, who was born with misshapen face. (所给词的适当形式填空)语法填空Amazon is publishing a new and improved Kindle. It’s 56 (thin) and lighter than the former one, and has a rounded design that makes it easier for one 57 (hold) it with one hand. But what’s most interesting is its characters for 58 blind.The previous fourth-generation Kindle Touch, which 59 (come) out in 2011, has speakers, headphone jacks, and text-to-speech functions. It is the last Kindle 60 is accessible to those who have trouble seeing text. When Amazon updated its LCD-screen Fire tablets, the company removed the audio character from the Kindle’s e-reader line, thus 61 (make) it inaccessible to blind users. The new Kindle will come with Bluetooth wireless technology. Much like Amazon’s voice-controlled Echo, the new Kindle reads e-books aloud when 62 (connect) to bluetooth headphones or speakers. How easy it will be for blind people to pair the Kindle with a bluetooth audio device will 63 (true) determine its accessibility. According to Amazon, the new Kindle may have no 64 (difficult) in pairing with bluetooth, as long as the host device has good text-to-speech technology, such as a built-in screen reader.65 Amazon isn’t the only e-book seller choice for blind people, it has a majority share of the US e-book market, according to The journal.66. 假定你是李华，正在新西兰读书。

表观遗传与环境

REVIEW PAPEREnvironmental epigenetics:prospects for studying epigenetic mediation of exposure–response relationshipsVictoria K.Cortessis •Duncan C.Thomas •A.Joan Levine •Carrie V.Breton •Thomas M.Mack •Kimberly D.Siegmund •Robert W.Haile •Peter irdReceived:21February 2012/Accepted:7June 2012/Published online:28June 2012ÓThe Author(s)2012.This article is published with open access at Abstract Changes in epigenetic marks such as DNA methylation and histone acetylation are associated with a broad range of disease traits,including cancer,asthma,metabolic disorders,and various reproductive conditions.It seems plausible that changes in epigenetic state may be induced by environmental exposures such as malnutrition,tobacco smoke,air pollutants,metals,organic chemicals,other sources of oxidative stress,and the microbiome,particularly if the exposure occurs during key periods of development.Thus,epigenetic changes could represent an important pathway by which environmental factors inﬂu-ence disease risks,both within individuals and across generations.We discuss some of the challenges in studyingepigenetic mediation of pathogenesis and describe some unique opportunities for exploring these phenomena.Abbreviations ART Assisted reproductive technologies ASM Allele-speciﬁc DNA methylation ChIP Chromatin immunoprecipitation CIMP CpG island methylator phenotype CpG Cytosine-phosphate-guanine dinucleotide CRC Colorectal cancer DES Diethylstilbestrol feNO Fractional exhaled nitric oxide FFPE Formalin-ﬁxed parafﬁn-embedded HDAC Histone deacetylases iNOS Inducible nitric oxide synthase IUGR Intra-uterine growth restriction IVF In vitro fertilizationPBMCs Peripheral blood mononuclear cells PTS Maternal smoking during pregnancy SNP Single nucleotide polymorphismBackgroundThe ﬁeld of epigenetics grew from attempts,beginning over 70years ago,to understand mechanisms whereby multiple cellular phenotypes arise from a single genotype during the complex process of developmental morpho-genesis termed epigenesis.The term ‘‘epigenetics’’was initially reserved for mechanisms by which phenotypic state,as determined by differential gene expression,could be stably retained through cell division by non-genetic factors.Various mechanisms have been proposed to have the potential to encode this phenotypic information;these include enzymatic methylation of cytosine bases (DNAV.K.Cortessis and D.C.Thomas contributed equally to this work.V.K.Cortessis ÁA.J.Levine ÁT.M.Mack ÁR.W.HaileDepartment of Preventive Medicine,Keck School of Medicine,University of Southern California,USC Norris Comprehensive Cancer Center,1441Eastlake Avenue,Los Angeles,CA 90089,USA D.C.Thomas (&)Department of Preventive Medicine,Keck School of Medicine,University of Southern California,2001N.Soto St.,SSB-202F,Los Angeles,CA 90089-9234,USA e-mail:dthomas@C.V.Breton ÁK.D.SiegmundDepartment of Preventive Medicine,Keck School of Medicine,University of Southern California,2001N.Soto St.,Los Angeles,CA 90089-9234,USAirdDepartments of Surgery,Biochemistry and Molecular Biology,Keck School of Medicine,University of Southern California,USC Norris Comprehensive Cancer Center,Epigenome Center,1441Eastlake Avenue,Los Angeles,CA 90089-9601,USAHum Genet (2012)131:1565–1589DOI 10.1007/s00439-012-1189-8methylation),post-translational modiﬁcation of tail domains of histone proteins(histone modiﬁcations)and associated nucleosome positioning or chromatin remodel-ing,non-coding RNAs,and transcription factor regulatory networks(Ptashne2007).Epigenetic marks established by each of these processes are often shared within a cell lineage; however,whether all persisting epigenetic marks satisfy requirements for stable transmission through cell division or some are merely reestablished from other information fol-lowing mitosis remains a vigorously debated question.The term epigenetics has more recently been used in the scientiﬁc literature to describe various unspeciﬁed non-genetic mechanisms inﬂuencing phenotype.This broader usage emerged from mouse studies addressing transgen-erational nutritional effects on phenotype,as well as human studies of phenotypic differences between monozygotic twins.In the popular press‘‘epigenetics’’has become almost synonymous with nutritional and environmental inﬂuences on gene expression.Thus,while‘‘epigenetics’’initially referred to largely self-contained developmental processes,it has come to describe environmental inﬂuences on phenotypic readout of genotypes.This semantic evo-lution has caused confusion and controversy regarding the meaning of‘‘epigenetics’’at a time of intensiﬁed interest in the possible role of epigenetic mechanisms in disease.In this review we deﬁne as epigenetic processes those that stably affect gene expression through mechanisms not involving the primary nucleotide sequence,and epigenetic state as the conﬁguration of chromatin and DNA marks utilized by these processes.By contrast,genetic state is widely understood to refer to the primary nucleotide sequence itself,while genetic processes maintain or change nucleotide sequence.Epidemiologic research addressing epigenetic mecha-nisms as mediators of environmental exposures on disease risk is constrained by important ethical considerations. These often preclude both experimental exposure to candi-date environmental causes,and invasive collection of cell types of greatest developmental and functional relevance to disease processes.Inquiry has therefore progressed largely by integrating information about biological mechanisms obtained in model systems with observational data provided by humans.To address the current state and future promise of this research,we undertook this review with two goals:to illustrate the potential of epigenetic processes to mediate exposure–phenotype relationships and to discuss study design and statistical analysis methods needed to investigate such mechanisms in relation to origins of human disease.We begin by discussing genetic,developmental,and environ-mental determinants of epigenetic state in human and model systems,then describe some of the diverse data implicating epigenetic mechanisms in various human diseases,both within individuals and across generations.We conclude by discussing technical challenges,suggesting promising opportunities for epidemiologic research in environmental epigenetics,and offering some thoughts about translational signiﬁcance and future directions of thisﬁeld. Determinants of epigenetic stateEpigenetic mechanisms work in concert to inﬂuence the potential for gene expression at myriad locations through-out the genome.The resulting epigenetic state of the gen-ome,termed epigenome,varies by cell type.Considering the tremendous diversity of epigenetic marks,which include dozens of different post-translational histone modiﬁcations and more than50million sites of potential DNA methylation in a diploid human genome(and thus [250M possible epigenotypes!),it seems that no two human cells would have identical epigenomes.Indeed,within each individual there are many epigenomes,and these change over time as a consequence of both normal developmental and pathological processes,as well as environmental exposures and random drift.Despite this potential for considerable variability of epigenetic patterns within and between individuals,there can also be remarkable consis-tency.In a study of11tissues in6autopsies,DNA meth-ylation patterns in a highly selected set of loci were found to be highly conserved,with intraclass correlations of0.85 across tissues within individuals and0.83across individ-uals within tissues(Byun et al.2009).The authors inter-preted these patterns as revealing different sets of person-speciﬁc and tissue-speciﬁc differentially methylated genes, anticipating subsequently observed differential genetic and acquired determination(Waterland et al.2010).DNA methylation has been the epigenetic mark most extensively measured in epidemiologic research for numerous reasons.It is of fundamental biological interest owing to its unambiguously stable transmission during cell division.It also has practical advantages:as a chemically stable covalent change to the DNA itself,DNA methylation is the only epi-genetic mark that survives the DNA extraction and puriﬁca-tion that is routine in molecular sample processing,and it can endure decades of archival sample storage(Kristensen et al. 2009).Genetic inﬂuencesNucleotide sequence is a primary determinant of epigenetic state,clearly evident from the distribution of epigenetic marks across the genome,determined in part by direct effects of G:C content and CpG(cytosine-phosphate-guanine dinucleotide) density(Tanay et al.2007;Thomson et al.2010).Additional genetic inﬂuences include proximity to repetitive elements such as Alu and LINE1(Estecio et al.2010),nucleararchitecture(Berman et al.2011),and binding sequences for transacting proteins(Bell et al.2011b;Weth and Renkawitz 2011).Motif searches and screening strategies have identiﬁed sequence elements that predispose to particular epigenetic states(Feltus et al.2006;Ideraabdullah et al.2011;Keshet et al.2006;Lienert et al.2011).Several lines of evidence indicate that genetic poly-morphisms can affect epigenetic state.Greater differences were observed between dizygotic co-twins than between monozygotic co-twins in two forms of epigenetic state: skewed patterns of X-inactivation,and DNA methylation at differentially methylated regions of the imprinted IGF2/ AH19locus(Wong et al.2011;Heijmans et al.2007; Ollikainen et al.2010).Extensive DNA methylation anal-yses in a multigenerational family revealed that epiallelic similarity was greater amongﬁrst-degree relatives than among more distantly related family members.In the same study,analyses addressing both genetic variation and DNA methylation identiﬁed widespread occurrence of allele-speciﬁc DNA methylation(ASM)that was associated with polymorphic nucleotides located near the DNA methyla-tion site,but not parent of origin.Authors of this report concluded that the majority of such ASM events depend on cis-acting DNA sequence(Gertz et al.2011).Such ASM events have yet to be characterized in large population-based studies,but more modest studies addressing hetero-zygous non-imprinted loci have identiﬁed widespread ASMs associated with nearby genotypic polymorphisms in DNA from multiple tissue types(Kerkel et al.2008;Tycko 2010;Schalkwyk et al.2010),as well as allele-speciﬁc chromatin structure and transcription factor binding in lymphoblastoid cell DNA(McDaniell et al.2010,reviewed in Birney et al.2010).Presumed transgenerational inheri-tance of epigenetic changes(‘‘epimutations’’)in the MLH1 (Suter et al.2004)and MSH2(Chan et al.2006)mismatch repair genes,both associated with colorectal cancer,were also traced to germline genetic variation.In the case of the MSH2 epimutation,deletion of a gene immediately upstream of the MSH2gene causes transcription to run through the MSH2 promoter,causing somatic hypermethylation and gene silencing(Ligtenberg et al.2009).The MLH1epimutation was found to be caused by a polymorphism in the50UTR of the MLH1gene,reducing transcriptional activity,and pre-disposing to aberrant somatic DNA methylation in each generation(Hitchins et al.2011).Developmental programming of the epigenomeIn successful mammalian reproduction,the single-cell zygote gives rise to an organism with hundreds of cell types.These diverse cellular phenotypes arise from the same shared genomic sequence by control of the subset of genes expressed in each cell type.Cellular differentiation is tightly linked to extensive erasure and establishment of lineage-speciﬁc epi-genetic marks,a process termed epigenetic reprogramming. Relatively detailed descriptions of DNA methylation in developing tissues have been carried out in the mouse,which serves as a model of epigenetic reprogramming in mammalian development(Trasler2009).At fertilization,reprogramming begins with extensive erasure of methyl marks in DNA of the paternal(sperm-derived)DNA,followed by more general loss of methyl marks in the zygote and embryo during cleavage divisions,while sparing parent-of-origin speciﬁc imprints.By the blastocyst stage,de novo DNA methylation distinguishes inner cell mass cells(from which embryonic lineages arise to create fetal structures)from relatively hypomethylated trophectoderm cells(from which extra-embryonic lineages arise to create transient structures,including placenta)(Fig.1).Germ cell lineage speciﬁcation begins in cells of the proximal epiblast,and involves a second extensive erasure of DNA methylation that removes parental imprint marks (Fig.1).Thereafter,the germ line develops in a sexually dimorphic fashion.New DNA methyl marks are established over many stages,extending through sexual maturity in accordance with the sex of the developing individual.At this time,the sex-speciﬁc imprint marks that govern parent-of-origin speciﬁc expression of imprinted genes in the sub-sequent generation are established(Faulk and Dolinoy2011).Developmental reprogramming can result in dramatic epigenetic differences between the two alleles.The asso-ciation between mono-allelic gene expression and DNA methylation has long been recognized,both in the context of X-inactivation in females(Boggs et al.2002;Sharp et al. 2011)and in parent-of-origin determined genomic imprinting(Ferguson-Smith2011),but now also in the mono-allelic expression of non-imprinted autosomal loci (Harris et al.2010;Tarutani and Takayama2011).Further resetting of epigenetic marks accompanies differ-entiation of many specialized cell types of the body as well as placenta and other transient structures during pregnancy,and subsequent development of body structures during various postnatal stages of development.Chromatin states that arise during development can affect the propensity to subsequent epigenetic change.An example of this is the predisposition of polycomb-repressive complex occupied genes in stem cells to the acquisition of DNA methylation abnormalities in aging and cancer(Ohm et al.2007;Schlesinger et al.2007; Teschendorff et al.2010;Widschwendter et al.2007).Environmental inﬂuencesMultiple differences in gene expression,presumably reﬂecting intrauterine epigenetic differences,have been identiﬁed in several tissues from newborn identical twins (Gordon et al.2011).The global methylation pattern ofindividuals changes with increasing age (Bjornsson et al.2008),as does the difference in global methylation between MZ twin pairs (Fraga et al.2005).Genetically identical MZ twins show some epigenetic discordance at birth,as indi-cated by gene expression discordance (Gordon et al.2011).Even over the ﬁrst decade of life (Wong et al.2010),and as aging adults (Talens et al.2010),MZ twins acquire addi-tional differences in epigenetic state,which may partly reﬂect different exposure histories,as would be expected if environmental exposures inﬂuence epigenetic state.How-ever,stochastic drift in epigenetic state and related con-sequences such as mono-allelic expression described in the previous section is likely responsible for much of the observed divergence.Therefore,other forms of data (dis-cussed below)are needed to determine what type of exposures may inﬂuence epigenetic state and the extent of resulting changes.Experimental studiesThe most direct evidence suggesting that ambient exposures may inﬂuence epigenetic state is experimental.In vitro studies have demonstrated associations of DNA methylation with various metals (Dolinoy et al.2007b ;Wright and Baccarelli 2007).In the in vivo setting,prenatal protein restriction is associated with hypomethylation of the gluco-corticoid receptor (GR )and PPAR a gene promoter regions inrat liver (Lillycrop et al.2005),changes that were prevented by folic acid supplementation (Lillycrop et al.2005)and which were transmitted to the F2generation (Burdge et al.2007).Plagemann et al.(2009)found hypermethylation in the promoter of the anorexigenic gene for proopiomelano-cortin in rats overfed as neonates.Whether this change could be transmitted to offspring was not assessed.DNA from sperm of mice exposed to steel plant air was found to be persistently hypermethylated long after exposure ended (Yauk et al.2008).Additionally,maternal nurturing behav-ior has been shown to modify methylation at individual CpG sites in the ngf1a binding region of the GR gene in the hip-pocampus of the offspring (Weaver et al.2004),an epige-netic modiﬁcation that persisted both into adulthood to modify response to stress,and into the F2generation.Human studiesChristensen and Marsit (2011)and Terry et al.(2011)have provided comprehensive reviews of environmental inﬂu-ences on epigenetic state in humans.Here we note expo-sure periods of particular interest and several examples of environmental exposures reportedly associated with epi-genetic state of speciﬁc human cell types.The epigenome may be most vulnerable to environ-mental insults during periods of extensive epigenetic reprogramming,which may in theory be disruptedbyFig.1Reprogramming ofDNA methylation in the zygote,early embryo,and primordial germ cells.Thickness of the outer arrows indicates levels of DNA methylation.Red maternal genome,blue paternal genome,black diploid genome.Embryonic lineages arise from cells of the inner cell mass (ICM),the placenta and extraembryonic membranes from trophectoderm cells,and the germ cell lineage fromprimordial germ cells following their determination fromproximal epiblast.Inner circles indicate developmental stages when key elements ofepigenetic programming are thought to occur (Adapted from Feng et al.2010)exposures that interfere with any process that governs reprogramming.Periods of particular vulnerability may therefore include the early stages of embryonic develop-ment mentioned above.Childhood is also proposed as a period of vulnerability,especially in the germline of females,since oocytes remain in a haploid de-methylated state until puberty,so environmental insults may poten-tially disturb the epigenetic state of the oocyte for many years(Faulk and Dolinoy2011),with potential implica-tions for both fertility and initial epigenetic state of off-spring of an exposed female.Somatic changes to DNA methylation may also result from environmental exposures in adults,as have been observed in aging and disease processes such as cancer described in the next section. Energy and nutrient intakeSigniﬁcant epigenetic changes in the IGF2gene have been documented in those prenatally exposed to severe caloric restriction during the Dutch hunger winter of World War II (Heijmans et al.2008).Hughes et al.(2009)additionally found that those most likely to be exposed to this famine during adolescence or young adulthood had a signiﬁcantly decreased risk of developing colorectal cancers(CRC) characterized by the CpG island methylator phenotype (CIMP),suggesting a role for early life exposures in CIMP-speciﬁc CRC pathogenesis.Folates are the major source of the methyl groups used for DNA and histone methylation.One study of folates and other one-carbon nutrients reported a differential effect of folate on the risk of the CIMP CRC subset compared to the non-CIMP subset(Van Guelpen et al.2010),while two other studies did not(Slattery et al.2006;van den Donk et al.2007).Most studies of the microsatellite instability high subset,characterized by hypermethylation of the MLH1gene promoter region and CIMP(Weisenberger et al.2006),have yielded similarly negative results(Eaton et al.2005;Schernhammer et al.2008;Slattery et al.2001; Wark et al.2005).On the other hand,in some studies the association between intake of alcohol(which degrades folates)and CRC risk has been reported to be greater in MSI-H and CIMP tumors(Diergaarde et al.2003;Eaton et al.2005;Slattery et al.2001).Micro-RNAs(miRNAs)are very short non-coding RNA molecules that can downregulate protein-coding genes by destabilizing mRNAs or blocking translation.The possi-bility that exogenous microRNA consumed in food may epigenetically regulate gene expression has emerged from recent studies demonstrating the presence of plant-derived miRNAs in sera of humans and other mammals(Zhang et al.2012).One of these plant microRNAs,MIR168a, which was demonstrated to be only of plant origin in control mice,binds coding sequence of the mammalian LDLRAP1 gene in vitro.Functional consequences in mammalian sys-tems were demonstrated experimentally,as MIR168a administered in vitro and during in vivo feeding studies decreased expression of the protein product of LDLRAP1. This line of research suggests novel epigenetic mechanisms whereby diet may modify risk of human disease.Air pollutionEmerging evidence suggests that air pollutants can inﬂu-ence epigenetic changes,including DNA methylation as well as up-or down-regulation of miRNAs(Jardim2011). In human epidemiologic studies,PM2.5and PM10expo-sures are associated with hypomethylation of Alu and/or LINE1elements in leukocytes and buccal cells(Baccarelli et al.2009;Bollati and Baccarelli2010;Madrigano et al. 2011;Salam et al.2012;Tarantini et al.2009),as well as altered DNA methylation in NOS2A,a gene involved in production of nitric oxide(Salam et al.2012;Tarantini et al.2009).Living in highly polluted cities(high PM and ozone)is also associated with hypermethylation of FOXP3 in regulatory T cells(Nadeau et al.2010),while neonates who were prenatally exposed to polyaromatic hydrocarbon (PAH)had hypermethylated ACSL3in DNA of umbilical cord white blood cells(Perera et al.2009);notably,both of these genes are involved in asthma pathogenesis.PAHs are also associated with hypermethylation of LINE1and Alu (Pavanello et al.2009;Perera et al.2009).More limited evidence is emerging to suggest that air pollution is asso-ciated with changes in miRNA expression(Bollati et al. 2010;Jardim2011),and adverse effects of air pollution constituents may be modiﬁed by variant alleles of genes involved in miRNA processing(Wilker et al.2010). Tobacco smokeFetal exposure to maternal smoking during pregnancy (PTS)is associated with reduced methylation of several repeated sequences,including Sat2(Flom et al.2011),Alu, and LINE1among children with the GSTM1null genotype (Breton et al.2009).PTS exposure is also associated with increased DNA methylation in speciﬁc genes,such as AXL and PTPRO(Breton et al.2009,2011b)and IGF2(Murphy et al.2011).In adult lung cancer patients,quantity and duration of active smoking as well as second-hand smoke is associated with increased DNA methylation of p16(Kim et al.2001;Scesnaite et al.2012),MGMT,and DAPK (Russo et al.2005).Tobacco smoke is also associated with tumor cell DNA methylation changes in esophageal squa-mous cell carcinoma(Huang et al.2011),signiﬁcantly higher frequencies of abnormal DNA hypermethylation inprostate(Enokida et al.2006)and gastric cancers tumor cells(Nan et al.2005)and with a higher risk of CIMP?colorectal tumors(Limsui et al.2010;Samowitz et al.2006).Lastly,the F2RL3gene is hypomethylated in smokers and may mediate the detrimental impact of smoking on cardiovascular mortality,since hypomethylat-ed F2RL3was found to be strongly associated with car-diovascular mortality among patients with stable coronary heart disease(Breitling et al.2012).Oxidative stressReactive oxygen species(ROS)are involved in numerous cellular processes including cellular redox alterations, immune response,signaling pathways,chromatin remod-eling and gene expression(Sundar et al.2010).ROS have the potential to inﬂuence epigenetic mechanisms(Baccar-elli and Bollati2009),and have been shown to inhibit binding of methyl-CpG binding protein2,a critical epi-genetic regulator that recruits cytosine methyl transferases and histone deacetylases to DNA(Valinluck et al.2004). Numerous environmental exposures,including constituents of air pollution and tobacco smoke,can generate ROS and thus may potentially alter epigenetic processes through oxidative stress mechanisms.MetalsPrenatal lead exposure is associated with decreased meth-ylation of LINE1and Alu in cord blood(Pilsner et al. 2009),and a similar pattern of LINE1methylation was reported in an elderly cohort(Wright et al.2010).Studies in humans have shown that arsenic exposure is associated with either global hypermethylation or hypomethylation in peripheral blood mononuclear cells(PBMCs)depending on dose(Majumdar et al.2010),as well as DNA hyperme-thylation of several genes,including CDKN2A(Chanda et al.2006),RASSF1A and PRSS3(Marsit et al.2006). Exposure to airborne particulates rich in lead,cadmium and chromium are associated with miRNA expression in peripheral blood(Bollati et al.2010)and airborne levels of nickel and arsenic are positively correlated with both his-tone3-lysine4trimethylation(H3K4me3)and histone 3-lysine9acetylation(H3K9ac)in blood leukocytes (Cantone et al.2011).Occupational exposure to nickel is associated with increased H3K4me3and decreased H3K9me2in PBMCs(Arita et al.2011).Lastly,cadmium can induce overexpression of the DNA methyltransferase genes DNMT1and DNMT3a in human embryo lung ﬁbroblasts,and is associated with hypermethylation and silencing of the MSH2,ERCC1,XRCC1and OGG1genes in human bronchial epithelial cells(Jiang et al.2008;Zhou et al.2011).Organic chemicalsGas-station attendants and police ofﬁcers occupationally exposed to low levels of benzene were found to have signiﬁcantly lower LINE1and Alu methylation,hyper-methylation of p15,and hypomethylation of MAGE-1in blood(Bollati and Baccarelli2010;Bollati et al.2007).Genetic9epigenetic9environmental interactionsMost work investigating effects of environmental factors on epigenetic state has not considered the potential for genetic susceptibility to modify these associations.However,Salam et al.(2012)recently investigated contributions of both genetic and epigenetic variation in air pollution-mediated levels of fractional exhaled nitric oxide(feNO).Measure-ment of feNO provides an in vivo summary assessment of inducible nitric oxide synthase(iNOS)activity as well as airway inﬂammation.These investigators found interrelated effects of exposure to the air pollution constituents PM2.5, NOS2A promoter haplotypes,and methylation of the iNOS encoding gene NOS2A and NOS2promotor haplotypes on feNO level.These observations illustrate not only the feasi-bility of assessing interactions between epigenetic,genetic, and environmental factors,but also the importance of doing so in order to delineate complex biological relationships and identify susceptible subpopulations.Epigenetic effects in human diseaseConditions associated with improper parental contributions of imprinted genes are currently the clearest examples of human diseases related to epigenetic state.Even before genomic imprinting was described,experiments in which pronuclei were transplanted into enucleated eggs demon-strated that both maternal and paternal chromosomal con-tributions are required for normal development.Control conceptuses receiving one set(haploid genome)of mater-nal(egg-derived)and one set of paternal(sperm-derived) chromosomes could develop normally.However,abnormal development and early demise occurred in all conceptuses receiving either two maternal sets or two paternal sets of chromosomes(McGrath and Solter1984),which devel-oped into tissues with histologic features of dermoid cysts and hydatiform moles,respectively.Model imprinting disorders such as Beckwith–Wiede-mann,Angelman,Russell–Silver,and Prader–Willi syn-dromes are human conditions that can be caused by aberrant epigenetic state(Ferguson-Smith2011).The speciﬁc features,early onset,and rarity of these disorders facilitated recognition of their relation to improper parental contributions of imprinted loci(e.g.two maternal or two。

约翰·济慈（John·Keats）--明亮的星（Bright

约翰·济慈（John·Keats）--明亮的星（Bright Star）明亮的星（Bright Star）是济慈写给⼥友芳妮-布劳恩（Fanny Brawne）的⼀⾸⼗四⾏诗。

在本诗中，济慈采⽤了bright star，the moving waters，snow，love's ripening breast等意象，把关于爱情、死亡和永恒的思想融会在⼀起，表现了⽣活、死亡、爱情和理想等永恒的主题。

Bright Starby John KeatsBright star, would I were steadfast as thou art---Not in lone splendour hung aloft the nightAnd Watching, with eternal lids apart,Like nature's patient, sleepless Eremite,The moving waters at their priestlike taskOf pure ablution round earth's human shores,Or gazing on the new soft-fallen maskOf snow upon the mountains and the moors---No-yet still steadfast, still unchangeable,Pillow'd upon my fair love's ripening breast,To feel for ever its soft fall and swell,Awake for ever in a sweet unrest,Still, still to hear her tender-taken breath,And so live ever---or else swoon to death.[2]明亮的星约翰·济慈明亮的星，但愿我能如你坚定---但并⾮孤独地在夜空闪烁⾼悬，睁着⼀双永不合拢的眼睛，犹如苦修的隐⼠彻夜⽆眠，凝视海⽔冲洗尘世的崖岸，好似牧师⾏施净体的沐浴，或正俯瞰下界的荒原与群⼭被遮盖在轻轻飘落的雪罩⾥---并⾮这样---却永远坚定如故，枕卧在我美丽的爱⼈的胸膛，永远能感到它的轻轻的起伏，永远清醒，在甜蜜的不安中，永远、永远听着她轻柔的呼吸，永远这样⽣活---或昏厥⽽死去。

Hormonesarethebody

Human Biology Book Ch. 4.2Hormones are the body's chemical messengers.Imagine you're seated on a roller coaster climbing to the top of a steep incline. In a matter ofmoments, your car drops hundreds of feet. You might notice that your heart starts beatingfaster. You grab the seat and notice that your palms are sweaty. These are normal physicalresponses to scary situations. The e ndocrine system c ontrols the conditions in your body bymaking and sending chemicals from one part of the body to another. Most responses of theendocrine system are controlled by the nervous system.H ormones a re chemicals that are made in one organ and travel through the blood to target cells. Target cells respond to the chemical. Many hormones, as you can see in the table below, affect all the cells in the body.Because hormones are made at one location and function at another, they are often called chemical messengers. When the hormone reaches its target cells, it binds to receptors on the surface of or inside the cells. There the hormone begins the chemical changes that cause the target cells to function in a specific way. All of the functions of the endocrine system work automatically, without your conscious control.Different types of hormones perform different jobs. Some of these jobs are to control the production of other hormones, to regulate the balance of chemicals such as glucose and salt in your blood, or to produce responses to changes in the environment. Some hormones are made only during specific times in a person's life. For example, hormones that control the development of sexual characteristics are not produced during childhood. When production begins in adolescence, these hormones cause major changes in a person's body.Glands produce and release hormones.The main structures of the endocrine system are groups of specialized cells called g lands.Many glands in the body produce hormones and release them into your circulatory system. As you can see in the illustration on page 113, endocrine glands can be found in many parts of your body. However, all hormones move from the cells in which they are produced to target cells.Pituitary Gland The pituitary (pih-TOO-ih-T EHR-ee) gland can be thought of as the director of the endocrine system. The pituitary gland is the size of a pea and is located at the base of the brain—right above the roof of your mouth. Many important hormones are produced in the pituitary gland, including hormones that control growth, sexual development, and the absorption of water into the blood by the kidneys.Hypothalamus The hypothalamus (H Y-poh-THAL-uh-muhs) is attached to the pituitary gland and is the primary connection between the nervous and endocrine systems. All of the secretions of the pituitary gland are controlled by the hypothalamus which produces hormones with releasing functions.Pineal Gland The pineal (PIHN-ee-uhl) gland is a tiny organ about the size of a pea. It is buried deep in the brain. The pineal gland is sensitive to different levels of light and is essential to rhythms such as sleep, body temperature, reproduction, and aging.Thyroid Gland You can feel your thyroid gland if you place your hand on the part of your throat called the Adam's apple and swallow. What you feel is the cartilage surrounding your thyroid gland. The thyroid releases hormones necessary for growth and metabolism. The tissue of the thyroid is made of millions of tiny pouches, which store the thyroid hormone. The thyroid gland also produces the hormone calcitonin, which is involved in the regulation of calcium in the body.Thymus The thymus is located in your chest. It is relatively large in the newborn baby and continues to grow until puberty. Following puberty, it gradually decreases in size. The thymus helps the body fight disease by controlling the production of white blood cells called T-cells.Adrenal Glands The adrenal glands are located on top of your kidneys. The adrenal glands secrete about 30 different hormones that regulate carbohydrate, protein, and fat metabolism and water and salt levels in your body. Some other hormones produced by the adrenal glands help you fight allergies or infections. Roller coaster rides, loud noises, or stress can activate your adrenal glands to produce adrenaline, the hormone that makes your heart beat faster.Pancreas The pancreas is part of both the digestive and the endocrine systems. The pancreas secretes two hormones, insulin and glucagon. These hormones regulate the level of glucose in your blood. The pancreas sits beneath the stomach and is connected to the small intestine.Ovaries and Testes The ovaries and testes also secrete hormones that control sexual development.Other Organs Some organs that are not considered part of the endocrine system do produce important hormones. The kidneys secrete a hormone that regulates the production of red blood cells. This hormone is secreted whenever the oxygen level in your blood decreases. Once the hormone has stimulated the red bone marrow to produce more red blood cells, the oxygen level of the blood increases. The heart produces two hormones that help regulate blood pressure. These hormones, secreted by one of the chambers of the heart, stimulate the kidneys to remove more salt.Control of the endocrine system includes feedback mechanisms.As you might recall, the cells in the human body function best within a specific set of conditions. Homeostasis(H OH-mee-oh-STAY-sihs) is the process by which the body maintains these internal conditions, even though conditions outside the body may change. The endocrine system is very important in maintaining homeostasis.Because hormones are powerful chemicals capable of producing dramatic changes, their levels in the body must be carefully regulated. The endocrine system has several levels of control. Most glands are regulated by the pituitary gland, which in turn is controlled by the hypothalamus, part of the brain. The endocrine system helps maintain homeostasis through the action of negative feedback mechanisms.Negative FeedbackMost feedback mechanisms in the body are called negative mechanisms, because the final effect of the response is to turn off the response. An increase in the amount of a hormone in the body feeds back to inhibit the further production of that hormone.The production of the hormone thyroxine by the thyroid gland is an example of a negative feedback mechanism. Thyroxine controls the body's metabolism, or the rate at which the cells in the body release energy by cellular respiration. When the body needs energy, the thyroid gland releases thyroxine into the blood to increase cellular respiration. However, the thyroid gland is controlled by the pituitary gland, which in turn is controlled by the hypothalamus. Increased levels of thyroxine in the blood inhibit the signals from the hypothalamus and the pituitary gland to the thyroid gland. Production of thyroxine in the thyroid gland decreases.Positive FeedbackSome responses of the endocrine system, as well as other body systems, are controlled by positive feedback. The outcome of a positive feedback mechanism is not to maintain homeostasis, but to produce a response that continues to increase. Most positive feedback mechanisms result in extreme responses that are necessary under extreme conditions.For example, when you cut yourself, the bleeding is controlled by positive feedback. First, the damaged tissue releases a chemical signal.The signal starts a series of chemical reactions that lead to the formation of threadlike proteins called fibrin. The fibrin causes the blood to clot, filling the injured area. Other examples of positive feedback include fever, the immune response, puberty, and the process of childbirth.Balanced Hormone ActionIn the body, the action of one hormone is often balanced by the action of another. When you ride a bicycle, you are able to ride in a straight line, despite bumps and dips in the road, by making constant steering adjustments. If the bicycle is pulled to the right, you adjust the handlebars by turning a tiny bit to the left.Some hormones maintain homeostasis in the same way that you steer your bicycle. The pancreas, for example, produces two hormones. One hormone, insulin, decreases the level of sugar in the blood. The other hormone, glucagon, increases sugar levels in the blood. The balance of the levels of these hormones maintains stable blood sugar between meals.Hormone ImbalanceBecause hormones regulate critical functions in the body, too little or too much of any hormone can cause serious disease. When the pancreas produces too little insulin, sugar levels in the blood can rise to dangerous levels. Very high levels of blood sugar can damage the circulatory system and the kidneys. This condition, known as diabetesmellitus, is often treated by injecting synthetic insulin into the body to replace the insulin not being made by the pancreas.。

英美文学史(英国)知识点汇总

英美文学期末复习Chapter 1 The Old and Medieval Period 中古时期An Introduction ：❖最早的英国居民：Celts❖In 43AD , Roman conquered Britain, making the latter a province of Roman Empire.公元43年，罗马征服英国，将其变成罗马帝国的一个省份。

❖In 449 Jutes came to Britain to settle there. Following the Jutes came Angles and Saxons. 449年，朱特人定居英国，紧跟着是安格鲁和撒克逊人。

❖Germanic means the Anglos, the Saxons and the Jutes.日耳曼族包括了安格鲁、萨克逊和朱特人。

❖Anglo-Saxon poetry is bold and strong, mournful and elegiac in spirit.安格鲁撒克逊诗歌大胆而有力，悲伤且忧郁。

❖These tribes from Northern Europe together created the united kingdom--Anglo-Saxon England ("Angle-land").这些来自北欧的部落创建了联合王国--安格鲁撒克逊英格兰(in 449)❖Their dialects naturally grew into a single language called Angle-ish or English, the ancestor of the present-day English.他们的方言自然而然地成为了一种单一的语言--盎格鲁语或者英语。

❖The old English were divided into two groups: ①religious group ②secular group古英语诗歌被分成两类：①宗教②世俗❖The religious group is mainly on biblical theme.宗教诗歌通常以圣经为主题。

选必三UNIT 3复习学案Reading and Thinking

②We_as_individuals_can_also_reduce_our_“carbon_footprint”_by_restricting_the_amount_of_carbon_dioxide_our_lifestyles_produce.
③It_is_our_responsibility_to_seize__every_opportunity_to_educate_everyone_about_global_warming，along_with_its_causes_and_impacts，because_this_is_the_most_serious_issue_affecting_all_of_us_on_this_planet.
4．[句式分析]
[尝试翻译]我们有责任抓住每一个机会，教育每个人了解全球变暖，包括其成因和影响，因为这是影响这个星球上我们所有人的最严重的问题。
[板块一单词短语——点点清]
层级一高频词汇精讲
1．starvevi.&vt.(使)挨饿；饿死(☞starvationn．饿死；挨饿)
(1)starve to death饿死
In_2013，a_lot_of_people_were_shocked_by_a_news_photo_of_a_dead_polar_bear_that_was_found_on_Norway's_Arctic_island_of_Svalbard.
2．细读短文并找出描写“采取行动和措施”的句子
4．句型公式：(1)There is evidence that ...有证据表明……；(2)现在分词作结果状语
教材原句：There_is_strong_and_comprehensive_evidence_that(有充分而全面的证据表明)the rise in temperature has led to an increase in extreme weather and natural disasters worldwide，not onlycausing_serious_damage(造成了严重的破坏)，but alsocosting_human_lives(造成了人员伤亡)．

尊重自然之恩的英语作文

Respecting the gifts of nature is a fundamental principle that should be ingrained in our daily lives.Here are some key points to consider when writing an essay on this topic:1.Introduction to the Topic:Begin by introducing the concept of natures gifts and why they are important.Mention the various ways in which nature provides for our needs, such as clean air,water,food,and resources for shelter.2.Importance of Nature:Elaborate on the significance of nature in our lives.Discuss how it supports the ecosystem,provides habitats for countless species,and contributes to our mental and physical wellbeing.3.Examples of Natures Gifts:Provide specific examples of what nature offers us.This could include the oxygen we breathe,the food we eat,the water we drink,and the materials we use for various purposes.4.Human Impact on Nature:Discuss the negative impact human activities have had on nature.Mention deforestation,pollution,climate change,and the extinction of species as consequences of not respecting natures gifts.5.Consequences of Disrespecting Nature:Explain the repercussions of not valuing natures offerings.This could include natural disasters,loss of biodiversity,and health issues arising from environmental degradation.6.Ways to Respect Nature:Offer practical steps that individuals and societies can take to respect nature.This might involve reducing waste,recycling,conserving water,planting trees,and supporting policies that protect the environment.7.Personal Responsibility:Emphasize the role each person plays in respecting nature. Encourage readers to reflect on their own actions and consider how they can make a positive impact.8.Global Efforts and Cooperation:Discuss the importance of international cooperation in environmental conservation.Mention global initiatives and agreements aimed at protecting the environment,such as the Paris Agreement.9.Future Outlook:Conclude by looking forward to a future where humanity lives in harmony with nature.Discuss the potential for sustainable development and the importance of passing on a healthy planet to future generations.10.Call to Action:End the essay with a strong call to action,urging readers to take stepsto respect and protect natures gifts for the benefit of all living beings. Remember to use clear and concise language,provide evidence to support your points, and maintain a logical flow throughout the essay.。

humannature英文作文

humannature英文作文Human nature is complex and unpredictable. It can be both selfish and selfless, depending on the circumstances. People are capable of great acts of kindness and compassion, but they are also capable of cruelty and greed.At the core of human nature is the desire forconnection and belonging. We are social creatures, craving relationships and community. We seek out companionship and support, forming bonds with others that can last a lifetime.Despite our social nature, humans also have a tendency towards competition and conflict. We are driven by a desire to succeed, to be the best, to outdo others. This competitive spirit can lead to innovation and progress, but it can also create division and animosity.Human nature is influenced by a variety of factors, including genetics, upbringing, and environment. These factors shape our personalities, values, and beliefs,influencing how we interact with the world around us. Our experiences and relationships play a significant role in shaping who we are and how we behave.Ultimately, human nature is a complex and multifaceted phenomenon. It is a reflection of our capacity for both good and evil, for love and hate, for altruism and selfishness. It is what makes us human, with all our flaws and virtues, our contradictions and complexities.。

humanbiology英语作文

humanbiology英语作文Human Biology。

Introduction:Human biology is the study of the structure, function, and behavior of the human body. It encompasses various aspects of the human body, including anatomy, physiology, genetics, and evolution. Understanding human biology is crucial for advancements in medicine, healthcare, and overall well-being. In this article, we will explore the fascinating world of human biology and its significance in our lives.Body:1. Anatomy:Anatomy is the study of the structure of the human body. It involves examining the different organs, tissues, and systems that make up the human body. By understanding anatomy, we can comprehend how each part of the body functions and how they work together to maintain overall health. For example, studying the anatomy of the cardiovascular system helps us understand how the heart pumps blood and how blood vessels transport oxygen and nutrients throughout the body.2. Physiology:Physiology focuses on the study of how the different organs and systems in the body function. It explores the mechanisms behind various bodily processes such as digestion, respiration, circulation, and reproduction. By understanding physiology, we can gain insights into how our bodies work and how they respond to different stimuli. For instance, studying the physiology of the nervous system helps us understand how nerve cells transmit signals and how the brain processes information.3. Genetics:Genetics is the study of genes and heredity. It explores how traits are passed down from one generation to another and how genetic variations can influence an individual's susceptibility to certain diseases. Understanding genetics is crucial in the field of medicine, as it allows us to identify genetic disorders, develop targeted therapies, and make informed decisions about reproductive health. For example, genetic testing can help identify individuals who carry genes associated with inherited diseases, allowing them to make informed choices about family planning.4. Evolution:Evolutionary biology examines how humans and other organisms have evolved over time. It explores the processes of natural selection, adaptation, and genetic variation that have shaped the human species. By studying evolution, we can gain insights into our shared ancestry with other living organisms and understand the origins of certain traits and behaviors. For instance, studying the evolution of the human immune system helps us understand how it has developed to defend against a wide range of pathogens.Conclusion:Human biology is a vast and complex field that encompasses various disciplines. By studying human biology, we gain a deeper understanding of our own bodies, how they function, and how they have evolved over time. This knowledge is essential for advancements in medicine, healthcare, and overall well-being. As we continue to unravel the mysteries of human biology, we pave the way for new discoveries and innovations that will benefit humanity as a whole. Let us embrace the wonders of human biology and strive to unlock its full potential for the betterment of our species.。

humanbiology英语作文

humanbiology英语作文英文回答：Human biology is the scientific study of the structure, function, development, and evolution of humans. It is a multidisciplinary field that draws on a variety of disciplines, including anatomy, biochemistry, cell biology, genetics, immunology, microbiology, molecular biology, nutrition, pathology, pharmacology, and physiology.Human biology is important for a number of reasons. First, it provides us with a better understanding of ourselves. By studying human biology, we can learn about our bodies, how they work, and how to keep them healthy. Second, human biology can help us to develop new treatments for diseases. By understanding the causes of diseases, we can develop new drugs and therapies to treat them. Third, human biology can help us to understand our place in the natural world. By studying human evolution, we can learn about our origins and how we came to be the dominantspecies on Earth.There are a number of different ways to study human biology. Some researchers use laboratory animals to study human diseases and conditions. Others use human subjects to study the effects of different drugs and treatments. Still others use computer models to simulate human systems and processes.Human biology is a complex and fascinating field. The more we learn about human biology, the better we will be able to understand ourselves, treat diseases, and improve our quality of life.中文回答：人體生物學是對人體結構、功能、發育和進化的科學研究。

马斯克人体生物学

马斯克人体生物学（中英文实用版）Elon Musk, the renowned entrepreneur and CEO of SpaceX and Tesla, has often expressed his interest in human biology.In a recent interview, he stated, "I have always been fascinated by the complexity of the human body and how it functions." 埃隆·马斯克是一位著名的企业家和SpaceX和特斯拉的CEO，他经常表达对人类生物学的兴趣。

在最近的一次采访中，他表示：“我一直对人体的复杂性和其功能感到着迷。

”Musk"s fascination with human biology extends beyond mere curiosity.He believes that understanding the human body can lead to significant advancements in technology and medicine.马斯克对人类生物学的兴趣不仅仅停留在好奇阶段。

他认为，了解人体可以导致技术和医学的重大进步。

"The human body is a complex system that has evolved over millions of years.By studying it, we can gain valuable insights into how to design better machines and improve human health," Musk explained.“人体是一个复杂的系统，经过数百万年的进化。

关于human biology的英语阅读

Human biology is a fascinating andplex subject that explores the various aspects of the human body, from the molecular level to the functioning of the entire organism. It epasses a wide range of topics, including genetics, physiology, anatomy, and biochemistry, and provides valuable insight into the mechanisms that govern human health and disease. This article 本人ms to provide an overview of some key concepts in human biology, covering the following topics:1. The Structure and Function of CellsCells are the basic units of life, and they form the building blocks of all living organisms, including humans. The human body isposed of trillions of cells, each with its own specialized structure and function. Cells play a crucial role in various physiological processes, such as metabolism, growth, and the immune response. Understanding the structure and function of cells is essential for g本人ning insight into the underlying mechanisms of human biology.2. Genetics and InheritanceGenetics is the study of genes and heredity, and it plays a fundamental role in human biology. Genes are the units of heredity that are passed down from one generation to the next,and they cont本人n the instructions for building and m本人nt 本人ning the human body. Genetic variations can influence an individual's susceptibility to cert本人n diseases, as well as their physical tr本人ts and characteristics. By studying genetics and inheritance, scientists can g本人n a better understanding of human diversity and the genetic basis of inherited disorders.3. The Immune SystemThe immune system is aplex network of cells, tissues, and organs that work together to protect the body from harmful pathogens, such as bacteria, viruses, and parasites. It plays a critical role in defending the body ag本人nst infections and diseases, and it also contributes to the m本人ntenance of overall health and well-being. Understanding the functioning of the immune system is crucial for developing new strategies for preventing and treating immune-related disorders.4. Human AnatomyAnatomy is the study of the structure of the human body, and it provides important insights into the organization and function of various bodily systems. The human body consists of multiple organ systems, including the nervous system, the cardiovascular system, the respiratory system, and the digestive system. Eachof these systems has its own unique structure and function, and they work together to support the overall health and functioning of the human body.5. Physiology and BiochemistryPhysiology is the study of the functions and activities of living organisms, and it focuses on how the various physiological processes contribute to the overall functioning of the human body. Biochemistry, on the other hand, explores the chemical processes and substances that occur within living organisms, and it provides important insights into the biochemical basis of human health and disease. The study of physiology and biochemistry is essential for g本人ning aprehensive understanding of human biology.In conclusion, human biology is a multifaceted and dynamic field that epasses a wide range of topics, from the structure and function of cells to theplexities of genetics, physiology, and biochemistry. By delving into these various aspects of human biology, scientists can g本人n valuable insights into the mechanisms that govern human health and disease, and they can develop new strategies for preventing and treating a wide range of medical conditions. As our understanding of humanbiology continues to advance, it holds the potential to revolutionize the field of medicine and improve the health and well-being of people around the world.。

水下呼吸的帽子作文

水下呼吸的帽子作文Breathing underwater is a concept that has intrigued humans for centuries. The idea of being able to breathe freely beneath the surface of the water like a fish is something many people have dreamed of. However, as of now, such a feat is not possible for humans, and we must rely on artificial devices such as underwater breathing apparatuses to explore the depths of the ocean.水下呼吸是一个长久以来吸引人类的概念。

能够像鱼一样在水下自由呼吸的想法让许多人梦寐以求。

然而，目前为止，人类并不能像鱼那样自由呼吸水下，我们必须依赖于人工设备，比如水下呼吸器才能探索海洋的深度。

One such artificial device that has been developed to enable humans to breathe underwater is the underwater breathing helmet, also known as the diving helmet. This innovative piece of technology allows divers to descend to great depths and explore the ocean floor for extended periods of time. The helmet is connected to a source of air on the surface through a long hose, providing divers with a constant supply of breathable air.其中一种能让人类在水下呼吸的人工设备就是水下呼吸帽，也被称为潜水帽。

抹香鲸呼吸英语作文

抹香鲸呼吸英语作文The Majestic Breath of the Sperm WhaleThe ocean, an endless expanse of blue, is home to a remarkable creature that has captivated the hearts and minds of humans for centuries. The sperm whale, or Physeter macrocephalus, is a colossal marine mammal that stands as a testament to the wonders of the natural world. With its distinctive blunt head and powerful body, the sperm whale is a true icon of the deep, and its breath is a sight to behold.As the largest of the toothed whales, the sperm whale can grow to an impressive length of up to 20 meters and weigh as much as 57 metric tons. Its sheer size is a testament to its evolutionary adaptations, which have allowed it to thrive in the challenging environment of the ocean. The sperm whale's massive head, which can account for up to a third of its total body length, is home to a unique organ called the spermaceti organ. This organ is filled with a waxy substance that helps the whale regulate its buoyancy and dive to great depths in search of its primary prey, the giant squid.One of the most captivating aspects of the sperm whale is itsremarkable breathing pattern. Unlike many other marine mammals, the sperm whale does not need to surface for air as frequently as its counterparts. Instead, it can hold its breath for up to 90 minutes, diving to depths of up to 3,000 meters in search of food. This incredible feat of endurance is made possible by the whale's unique physiology, which includes a highly efficient respiratory system and the ability to conserve oxygen during its dives.As the sperm whale surfaces to breathe, it produces a distinctive "blow" – a powerful exhalation of air that can be seen from miles away. This breath is a true spectacle of nature, as the whale's massive body emerges from the water, its powerful lungs expelling a plume of water vapor and air that can reach heights of up to 6 meters. The sound of the whale's breath, a deep, resonant rumble, is equally captivating, echoing across the vast expanse of the ocean.The sperm whale's breath is not only a visual and auditory marvel but also a testament to the animal's remarkable adaptations. As the whale dives deep into the ocean, its body undergoes a series of physiological changes that allow it to withstand the immense pressure and lack of oxygen. Its heart rate slows, and its blood vessels constrict, redirecting blood flow away from non-essential organs and towards the brain and vital organs. This incredible feat of adaptation allows the sperm whale to thrive in an environment that would be inhospitable to most other creatures.Despite the sperm whale's impressive size and strength, it is not immune to the threats posed by human activity. Commercial whaling, pollution, and climate change have all taken a toll on sperm whale populations, with some estimates suggesting that their numbers have declined by as much as 30% over the past century. Conservation efforts, however, have helped to protect the sperm whale and its habitat, and there are signs that its population is beginning to recover.As we continue to explore and understand the ocean's mysteries, the sperm whale remains a captivating and awe-inspiring creature. Its breath, a powerful and majestic display of its strength and resilience, serves as a reminder of the incredible diversity and beauty of the natural world. By protecting and preserving the sperm whale and its habitat, we can ensure that future generations will be able to witness this remarkable sight and marvel at the wonders of the ocean.。

海洋生态系统生产者消费者英语作文

海洋生态系统生产者消费者英语作文The marine ecosystem is a complex and vibrant community that covers more than 70% of the Earth's surface. Within this vast environment, producers and consumers play vital roles in maintaining ecological balance and sustaining life. Understanding these roles is essential for appreciating the intricate web of life beneath the waves.Producers, primarily phytoplankton, kelp, and seagrasses, serve as the foundation of the marine food web. These organisms harness sunlight through the process of photosynthesis, converting it into energy. Phytoplankton, microscopic plants that drift in the ocean's upper layers, contribute significantly to global oxygen production and act as the primary source of food for many marine creatures. Kelp forests, found along coastlines, not only provide habitat and food for numerous species but also help in stabilizing theocean floor and preventing coastal erosion. Seagrasses, often overlooked, also play a crucial role by stabilizing sediments and providing refuge for various juvenile species.Consumers in the marine ecosystem can be categorized into three main groups: primary, secondary, and tertiary consumers. Primary consumers, such as zooplankton and small fish, feed directly on producers. Zooplankton, tiny aquatic creatures, consume phytoplankton and are a crucial food source for many larger animals. Secondary consumers include fish likemackerel and cod, which prey on primary consumers. Tertiary consumers, like sharks and large predatory fish, sit at thetop of the food chain, ensuring that the population of other marine species remains balanced.The interactions between producers and consumers create a dynamic equilibrium that is essential for the health of the marine ecosystem. For instance, if the population of primary consumers increases excessively, they may overconsumephytoplankton, leading to a decline in oxygen levels and impacting many species, including larger predators. Conversely, if tertiary consumers are removed from the ecosystem, there may be a surge in secondary consumers, which could also disrupt the balance and lead to overgrazing of primary consumers.Human activities, such as overfishing, pollution, and climate change, pose significant threats to this delicate balance. Overfishing has led to drastic declines in fish populations, affecting not only the targeted species but also the overall structure of the marine community. Pollution introduces harmful substances into the water, affecting both producers and consumers, while climate change leads to ocean warming and acidification, altering habitats and species distributions.In conclusion, the roles of producers and consumers in the marine ecosystem are interdependent and crucial formaintaining ecological balance. Protecting this intricate web of life is paramount, requiring concerted efforts to mitigate human impacts and promote sustainable practices. By understanding these roles, we can better appreciate the importance of preserving our oceans for future generations.。

humannature英语作文

humannature英语作文Human nature is a complex and multifaceted subject that has intrigued philosophers, writers, and scholars for centuries. It encompasses the fundamental characteristics and traitsthat make us human, including our emotions, desires, motivations, and behaviors.One of the most prominent aspects of human nature is our capacity for empathy and compassion. We have the ability to understand and share the feelings of others, which allows us to form deep connections and relationships. This empathy is what drives us to help those in need and to work together for the greater good.However, human nature also has a darker side. We are capable of selfishness, greed, and cruelty. Throughout history, we have seen countless examples of people acting out of self-interest, leading to conflict, oppression, and suffering. This darker side of human nature can be difficult to understand and accept, but it is an important part of who we are.Despite our flaws, human nature also includes a strong drive for growth and self-improvement. We have an innate desire to learn, explore, and push the boundaries of what is possible. This drive has led to incredible advancements in science, technology, and culture, and it continues to propel us forward.Ultimately, human nature is a fascinating and complex topic that is constantly evolving. It is a combination of our strengths and weaknesses, our light and dark sides. By understanding and embracing all aspects of human nature, we can strive to become better versions of ourselves and work towards a more compassionate and enlightened world.。

象人英文作文翻译

象人英文作文翻译"英文，"As a human, I believe that we all have a responsibility to protect and care for the environment. One way we can do this is by reducing our use of single-use plastics. For example, instead of using plastic straws, I always carry a reusable metal straw with me. This small change has made a big impact on reducing my plastic waste.Another way I contribute to protecting the environment is by conserving water. I make sure to turn off the tap while brushing my teeth and take shorter showers. These simple habits not only help to save water, but also reduce my water bill.I also try to reduce my carbon footprint by walking or cycling whenever possible instead of driving. Not only isit good for the environment, but it also helps me stay active and healthy.In addition, I make an effort to recycle as much as possible. I separate my recyclables from my regular trash and make sure to properly dispose of them. It's a small effort that can make a big difference in reducing the amount of waste that ends up in landfills.Overall, I believe that every little action counts when it comes to protecting the environment. By making small changes in our daily lives, we can all make a positive impact on the planet."中文，"作为一个人，我相信我们都有责任保护和关心环境。

Human biomarkers in breath by photoacoustic

安徽省合肥市庐阳区第六中学2025届高三下学期第五次调研考试英语试题含解析

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表观遗传与环境

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Hormonesarethebody

英美文学史(英国)知识点汇总

选必三UNIT 3复习学案Reading and Thinking

尊重自然之恩的英语作文

humannature英文作文

humanbiology英语作文

humanbiology英语作文

马斯克 人体 生物学

关于human biology的英语阅读

水下呼吸的帽子作文

抹香鲸呼吸 英语作文

海洋生态系统生产者消费者英语作文

humannature英语作文

象人英文作文翻译

马斯克人体生物学

抹香鲸呼吸英语作文