電大西方社會(huì)學(xué)形考作業(yè)1-4參考答案資料.doc

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作業(yè)一　思考題 　　 請比較分析以迪爾凱姆為代表的實(shí)證主義社會(huì)學(xué)和以韋伯為代表的人本主義社會(huì)學(xué)在思想來源、研究對象、方法原則等方面有何區(qū)別與聯(lián)系？（形成書面作業(yè)，字?jǐn)?shù)不少于400字） 作業(yè)二　階段性測驗(yàn)（第1至10章） 　　 一、單項(xiàng)選擇題（每小題2分，10小題，共20分。每小題備選答案中有一項(xiàng)正確答案，請將正確答案的序號填在括號內(nèi)） 　　 1．自1838年（D?。┨岢錾鐣?huì)學(xué)概念至今，僅僅170多年的歷史，社會(huì)學(xué)獲得了迅速發(fā)展?！　? A．韋伯　　B．斯賓塞　　C．迪爾凱姆　　D．孔德　　 2．孔德將（　B）作為社會(huì)學(xué)的兩大研究主題。　　 A．公平與正義　　B．秩序與進(jìn)步　　C．效率與公平　　D．個(gè)人與社會(huì)　　 3．斯賓塞認(rèn)為，根據(jù)社會(huì)管理調(diào)控方式進(jìn)行劃分，社會(huì)進(jìn)化類型是：（D?。I(yè)社會(huì)?！　? A．游牧社會(huì)　　B．農(nóng)業(yè)社會(huì)　　C．封建社會(huì)　　D．軍事社會(huì)　　 4．迪爾凱姆提出社會(huì)學(xué)的研究對象是（C?。??！　? A．社會(huì)現(xiàn)象　　B．社會(huì)規(guī)律　　C．社會(huì)事實(shí)　　D．社會(huì)組織　　 5．齊美爾提出要建立關(guān)于社會(huì)形式的社會(huì)（B?。??！　? A．物理學(xué)　　B．幾何學(xué)　　C．心理學(xué)　　D．動(dòng)力學(xué)　　 6．韋伯認(rèn)為社會(huì)學(xué)的研究對象是（　D）?！　? A．社會(huì)事實(shí)　　B．社會(huì)形式　　C．社會(huì)規(guī)律　　D．社會(huì)行動(dòng)　　 7．帕累托指出，大量的社會(huì)行為或社會(huì)事件都是（A　）的?！　? A．非邏輯　　B．合邏輯　　C．合理性　　D．合規(guī)律性　　 8．帕森斯認(rèn)為，動(dòng)機(jī)取向的社會(huì)行動(dòng)是行動(dòng)者以（D　）為爭取目標(biāo)的主觀要求。　　 A．價(jià)值理想　　B．社會(huì)進(jìn)步　　C．道德要求　　D．直接利益　　 9．默頓認(rèn)為，某種最初有益于社會(huì)行動(dòng)或社會(huì)結(jié)構(gòu)的功能，在后來演化過程中變成了有害于這種社會(huì)行動(dòng)或社會(huì)結(jié)構(gòu)的功能，這種功能稱之為（B ）。　　 A．隱功能　　B．功能失調(diào)　　C．反功能　　D．顯功能　　 10．米德提出有意義的意識過程都是在人際溝通或社會(huì)交往中展開的，它的最簡單、最基本的形式是（ C）?！　? A．情感溝通　　B．語言交流　　C．姿勢對話　　D．意義表達(dá)　　 二、填空題（每空1分，共15分） 　　 1．孔德認(rèn)為社會(huì)發(fā)展先后經(jīng)歷了神學(xué)階段、形而上學(xué)階段、實(shí)證階段三個(gè)不同的階段?！　? 2．齊美爾根據(jù)服從于多數(shù)人、服從于組織、服從于思想原則這三個(gè)標(biāo)準(zhǔn)對統(tǒng)治與服從的關(guān)系進(jìn)行了劃分?！　? 3．迪爾凱姆論述了利己性自殺、利他性自殺、失范性自殺等三種自殺類型?！　? 4．韋伯指出，理解社會(huì)行動(dòng)的基本形式是投入、體驗(yàn)和設(shè)身處地。　　 5．米德指出，游戲階段是嬉戲階段的發(fā)展，它的基本特點(diǎn)是復(fù)雜性、組織性、規(guī)則性和預(yù)期性 。　　 三、名詞解釋（每小題5分，4小題，共20分） 　　 1．實(shí)證階段（孔德）　　 孔德認(rèn)為，實(shí)證階段是超越了神學(xué)和形而上學(xué)虛幻性和絕對性的階段，是以實(shí)證科學(xué)為知識基礎(chǔ)，直接面向經(jīng)驗(yàn)事實(shí)的階段。 2．社會(huì)比率（迪爾凱姆）　　 社會(huì)比率是由個(gè)人行為或個(gè)別事實(shí)相互聯(lián)系而構(gòu)成的統(tǒng)計(jì)比例或計(jì)量關(guān)系，如出生率、死亡率、失業(yè)率等。 3．有機(jī)團(tuán)結(jié)（迪爾凱姆）　　 有機(jī)團(tuán)結(jié)是在現(xiàn)代工業(yè)社會(huì)中形成的社會(huì)團(tuán)結(jié)，它以社會(huì)高度分化、社會(huì)成員充分分工為基礎(chǔ)。在有機(jī)團(tuán)結(jié)中，維系社會(huì)成員的紐帶是因?yàn)樯鐣?huì)分工和社會(huì)專業(yè)化而造成的他們不可超越的相互依賴關(guān)系。 4．社會(huì)唯名論　　 韋伯的立場被稱為“社會(huì)唯名論”，其實(shí)質(zhì)是認(rèn)為那些諸如階層、階級、組織和社會(huì)比率等概念并不是實(shí)際存在，而是表達(dá)人們思想觀念的名詞，真正實(shí)在的是受主觀意愿支配而真實(shí)行動(dòng)著的人。 四、簡答題（每題10分，2道題，共20分） 1．帕森斯A—G—I—L框架中的適應(yīng)、目標(biāo)達(dá)到、整合與維模（即潛在的模式維持）的具體含義是什么？ 　　 答：A ——適應(yīng)(Adaptation)，即社會(huì)系統(tǒng)對環(huán)境的適應(yīng)功能。包括對環(huán)境給系統(tǒng)的限制和壓力的順應(yīng)，以及對環(huán)境的積極改造。 G——目標(biāo)達(dá)到(Goal-attainment)，即社會(huì)系統(tǒng)確立總目標(biāo)的功能。社會(huì)系統(tǒng)確立了總目標(biāo)，可以把社會(huì)成員的社會(huì)活動(dòng)集中指向某種目的。目標(biāo)達(dá)到功能表現(xiàn)為一種過程，包括確立目標(biāo)和組織社會(huì)成員為實(shí)現(xiàn)這一目標(biāo)而付諸實(shí)踐。 I——整合(Integration)，即協(xié)調(diào)社會(huì)系統(tǒng)各組成部分，使它們達(dá)到某種程度的團(tuán)結(jié)而開展有效的合作。整合功能是通過適當(dāng)情感聯(lián)系實(shí)現(xiàn)的 。 L——潛在的模式維持(Latency pattern maintenance)，即根據(jù)某些規(guī)范與原則，維持系統(tǒng)行動(dòng)秩序與活動(dòng)方式連續(xù)性的功能。 社會(huì)系統(tǒng)不會(huì)因?yàn)檫\(yùn)行的間歇性而中斷，它將通過一系列規(guī)范和原則使自己的運(yùn)行模式潛存下來，一旦社會(huì)成員進(jìn)入這些規(guī)范和原則作用的范圍內(nèi)，系統(tǒng)又重新運(yùn)行起來。 2．韋伯將社會(huì)行動(dòng)劃分為哪四種理想類型，其劃分的依據(jù)及每一種社會(huì)行動(dòng)的特點(diǎn)是什么？　　 韋伯將社會(huì)行動(dòng)劃分為： （1）情感類型：其特點(diǎn)是人們開展社會(huì)行動(dòng)時(shí)，把喜、怒、哀、樂等情感和情緒作為自己行動(dòng)的主要依據(jù)。 （2）價(jià)值理性類型：其特點(diǎn)是目的是給定的，行動(dòng)者不能根據(jù)自己的利益需求主動(dòng)地衡量和挑選何種行動(dòng)目標(biāo)。 （3）傳統(tǒng)類型：其特點(diǎn)是既不算功利，也不追求超功利的理想，它所堅(jiān)持的是習(xí)慣的繼續(xù)和歷史的沿襲。 （4）工具理性類型：其特點(diǎn)是具有功利目的性、手段選擇性、操作策化性、效果檢測性等特點(diǎn)。 這四種行動(dòng)類型劃分的依據(jù)是人們開展社會(huì)活動(dòng)的根據(jù)不同作出的劃分；它們都在一定普遍性程度概括了某些社會(huì)成員的行動(dòng)方式，亦即不是少數(shù)個(gè)別人的個(gè)別主觀性。 五、論述題（25分） 　　 1．默頓是如何批判宏觀結(jié)構(gòu)功能主義的？ 作業(yè)三　課堂討論 　 請討論布迪厄所論述的社會(huì)資本有哪些特點(diǎn)？舉例說明社會(huì)資本的開發(fā)和積累對于個(gè)人、組織和國家的發(fā)展有哪些好處？又會(huì)產(chǎn)生哪些問題？（每位同學(xué)于課堂討論之后，提交一份發(fā)言總結(jié)，字?jǐn)?shù)不少于400字） 答：根據(jù)布迪厄的說明，可以看出社會(huì)資本有如下的特點(diǎn)：首先，社會(huì)資本是一種從中可以吸取某種資源的、持續(xù)性的社會(huì)網(wǎng)絡(luò)關(guān)系。其次，社會(huì)資本是一種體制化的網(wǎng)絡(luò)關(guān)系，而不是那些靠親屬關(guān)系和血緣關(guān)系建立起來的自然聯(lián)系，是在特的工作關(guān)系、群體關(guān)系和組織關(guān)系中存在的，它要通過某種制度性的關(guān)系來加強(qiáng)，否則就是變動(dòng)不居的偶然聯(lián)系，而不是作為具有穩(wěn)定聯(lián)系的社會(huì)網(wǎng)絡(luò)。再次，社會(huì)資本具有潛在性和現(xiàn)實(shí)性。只有當(dāng)社會(huì)網(wǎng)絡(luò)被行動(dòng)者調(diào)動(dòng)或利用時(shí)，它才能以某種能量或資源發(fā)揮資本在實(shí)踐中的作用，這時(shí)它就是現(xiàn)實(shí)的社會(huì)資本；而當(dāng)它未被調(diào)動(dòng)和利用時(shí)，它僅僅是靜態(tài)的網(wǎng)絡(luò)關(guān)系，是潛在的社會(huì)資本，可見，社會(huì)資本是動(dòng)態(tài)的實(shí)踐性概念。最后，社會(huì)資本作為一種網(wǎng)絡(luò)資源，每一個(gè)被聯(lián)系在其中的社會(huì)成員都可以從中受益，但受益的程度要依每個(gè)人實(shí)踐能力的大小而有所區(qū)別。社會(huì)資本的開發(fā)和積累對于個(gè)人發(fā)展的好處和產(chǎn)生問題：例如社會(huì)資本對大學(xué)生就業(yè)的影響。1.社會(huì)資本對大學(xué)生就業(yè)具有積極的作用，但過度追求和使用社會(huì)資本會(huì)給當(dāng)事人及社會(huì)帶來極為不利的影響。社會(huì)資本與人力資本相互作用，對大學(xué)生就業(yè)過程產(chǎn)生協(xié)同效應(yīng)。社會(huì)資本對大學(xué)生就業(yè)的積極影響主要體現(xiàn)在：（1）社會(huì)資本可以幫助收集、篩選信息, 可以彌補(bǔ)大學(xué)畢業(yè)生就業(yè)信息的不對稱。2）社會(huì)資本可以幫助推薦就業(yè)。（3）社會(huì)資本有助于降低就業(yè)成本。（4）有助于大學(xué)生實(shí)現(xiàn)自主創(chuàng)業(yè)。2.社會(huì)資本在大學(xué)生就業(yè)中產(chǎn)生的消極影響：1）滋長了“權(quán)力和關(guān)系崇拜”。（2）滋長了嚴(yán)重的依賴思想。（3）極大地破壞了業(yè)已形成的“雙向選擇、自主擇業(yè)”的公平競爭的就業(yè)機(jī)制。（4）消解大學(xué)生去西部、下基層的熱情，加劇大學(xué)生就業(yè)難現(xiàn)狀。對于組織和國家的發(fā)展：隨著資本積累的進(jìn)行，一方面擴(kuò)大了生產(chǎn)規(guī)模，增加了社會(huì)財(cái)富；另一方面在生產(chǎn)出資本主義生產(chǎn)關(guān)系。第一，資本積累對促進(jìn)生產(chǎn)力的發(fā)展有重要作用。資本積累是擴(kuò)大再生產(chǎn)的源泉，是擴(kuò)大再生產(chǎn)的物質(zhì)保證；為科學(xué)技術(shù)的迅猛發(fā)展提供了物質(zhì)技術(shù)條件；推動(dòng)了資本和生產(chǎn)的集中，對于提高資本主義經(jīng)濟(jì)的社會(huì)化程度是非常有力的，從而為資本和生產(chǎn)的國家化發(fā)展提供了保障。第二，資本積累對促進(jìn)整個(gè)社會(huì)的物質(zhì)文明和社會(huì)進(jìn)步具有重要作用。隨著資本積累不斷擴(kuò)大，資本主義生產(chǎn)得到了迅速發(fā)展，社會(huì)財(cái)富日益增加，從而為社會(huì)各個(gè)部門的發(fā)展提供物質(zhì)和資金保證，特別是為了公共設(shè)施建設(shè)、科學(xué)教育和文化衛(wèi)生事業(yè)、社會(huì)福利等方面的建設(shè)提供了豐富的物資和資金保障。因此，從某種意義上說，資本積累對于提高整個(gè)社會(huì)的物質(zhì)文明和社會(huì)進(jìn)步具有一定的積極作用。產(chǎn)生的問題：資本積累一方面促進(jìn)了社會(huì)生產(chǎn)力的發(fā)展，另一方面不斷生產(chǎn)出日益擴(kuò)大的資本家階級。 社會(huì)財(cái)富日益積累在少數(shù)人手中，這是資本主義積累的特點(diǎn)之一。資本積累在帶給資本家階層日益富裕的同時(shí)，卻給無產(chǎn)階級帶來了日益的貧困。 作業(yè)四　階段性測驗(yàn)（第11至20章） 一、單項(xiàng)選擇題（每小題2分，10小題，共20分。每小題備選答案中有一項(xiàng)正確答案，請將正確答案的序號填在括號內(nèi)） 　　 1．霍曼斯認(rèn)為，（D）指人們在社會(huì)交換行為中為獲得某種利益，或?yàn)閷?shí)現(xiàn)某種目的而預(yù)先做出的支付?！　? A．幫助　　B．關(guān)愛　　C．友誼　　D．成本　　 2．布勞指出，一個(gè)人要想在社會(huì)中獲得權(quán)力，最有效的途徑就是向別人（B）?！　? A．顯示能力　　B．提供幫助　　C．開展競爭　　D．學(xué)習(xí)優(yōu)點(diǎn)　　 3．柯林斯展開沖突理論從微觀邁向宏觀研究所使用的核心觀念是（C）。 A．社會(huì)矛盾　　B．階級沖突　　C．互動(dòng)儀式鏈　　D．利益關(guān)系　　 4．常人方法學(xué)超越了（B）的對立?！　? A．唯物與唯心　　B．主觀與客觀　　C．個(gè)人與社會(huì)　　D．傳統(tǒng)與現(xiàn)代　　 5．丹尼爾貝爾認(rèn)為，知識階級成為后工業(yè)社會(huì)的主導(dǎo)力量，一個(gè)重要根據(jù)是（B）上升到首要地位。　　 A．生產(chǎn)技術(shù)　　B．理論知識　　C．發(fā)明創(chuàng)造　　D．文學(xué)藝術(shù)　　 6．?？轮鲝垼R考古學(xué)要在實(shí)證性的話語實(shí)踐中揭示出具有（C）的規(guī)則?！　? A．普遍性　　B．規(guī)律性　　C．差別性　　D．相似性　　 7． 布迪厄指出，人們在日常生活中的大量行為是由（D）支配的?！　? A．理性思維　　B．風(fēng)俗習(xí)慣　　C．宗教觀念　　D．實(shí)踐感　　 8．馬爾庫塞提出，本能革命的目的在于建設(shè)無壓抑性文明，而無壓抑性文明的根本點(diǎn)在于（D）的解放?！　? A．思想　　B． 人性　　C．理性　　D．愛欲　　 9．哈貝馬斯認(rèn)為，目的理性行動(dòng)中的規(guī)范結(jié)構(gòu)展開于主觀與客觀之間，亦即展開于（B）之間?！　? A．人與社會(huì)　　B．人與物　　C．人與群體　　D．人與人　　 10．吉登斯認(rèn)為，社會(huì)系統(tǒng)中的結(jié)構(gòu)是由人們頭腦中的（D）亦即結(jié)構(gòu)觀念指導(dǎo)人們的實(shí)踐行動(dòng)創(chuàng)造出來的?！　? A．理論觀念　　B．傳統(tǒng)觀念　　C．價(jià)值理想　　D．記憶痕跡　 二、填空題（每空1分，共15分） 　　 1．霍曼斯用成本與報(bào)酬關(guān)系來解釋社會(huì)交換權(quán)力形成的兩個(gè)原則是利益最小原則和稀有資源原則?！　? 2．貝爾認(rèn)為，后工業(yè)社會(huì)來臨的主要標(biāo)志有：從產(chǎn)品經(jīng)濟(jì)轉(zhuǎn)變?yōu)榉?wù)經(jīng)濟(jì)，人員處于主導(dǎo)地位，上升到首要地位?！　? 3．布迪厄論述了經(jīng)濟(jì)資本、文化資本、社會(huì)資本這三種資本形態(tài)及其相互關(guān)系?！　? 4．哈貝馬斯認(rèn)為，實(shí)現(xiàn)語言的有效溝通應(yīng)當(dāng)滿足以下四個(gè)條件，即表達(dá)的可領(lǐng)會(huì)性陳述的真實(shí)性、表達(dá)的真誠性、言說的正當(dāng)性?！　? 5．吉登斯認(rèn)為，傳遞性經(jīng)驗(yàn)是通過知識信息和通訊媒體而形成的間接性經(jīng)驗(yàn)?！　? 三、名詞解釋（每小題5分，4小題，共20分） 　　 1．利益最小原則（霍曼斯）　　 霍曼斯用成本與報(bào)酬的關(guān)系來解釋社會(huì)交換權(quán)力的形成。他認(rèn)為，在社會(huì)交換行為中，如果一個(gè)人在交換中付出的成本大于對方，而獲得的報(bào)酬卻小于對方，那么他在交換中將獲得支配對方和控制交換行為的權(quán)力?；袈狗Q之為“利益最小原則”。 2．內(nèi)部報(bào)酬（布勞）　　 內(nèi)部報(bào)酬是從社會(huì)交換關(guān)系本身獲得的報(bào)酬，內(nèi)部報(bào)酬從內(nèi)部交換獲得；內(nèi)部交換是帶有非功利色彩的情感方面的交換，例如友誼、戀愛就屬于內(nèi)部交換；由內(nèi)部交換而得到的內(nèi)部報(bào)酬具有非功利的情感性質(zhì)。 3．場域（布迪厄）　　 場域是以各種社會(huì)關(guān)系聯(lián)結(jié)起來的表現(xiàn)形式多樣的社會(huì)場合或社會(huì)領(lǐng)域，場域中有社會(huì)行動(dòng)者、團(tuán)體機(jī)構(gòu)、制度和規(guī)則等因素存在，場域的本質(zhì)是這些構(gòu)成要素之間的社會(huì)關(guān)系或社會(huì)網(wǎng)絡(luò)。 4．實(shí)踐意識（吉登斯）　　 實(shí)踐意識是有能力支配行為的感性意識；是介于無意識和話語意識之間的“只做不說的意識”；實(shí)踐意識具有日常性和慣例性。 四、簡答題（每題10分，2道題，共20分） 　　 1．丹尼爾貝爾論述的中軸原理的方法論意義是什么？　　 中軸原理具有突出的問題意識，中軸原理提出了社會(huì)學(xué)研究的針對性和功效性。 中軸原理不追求穩(wěn)定不變的普遍性原則，而是在動(dòng)態(tài)變化中不斷概括和回答各種新問題。不同的社會(huì)層面中有不同的中心因素或中軸原理，因此，不能用同一種因素作為解釋各種社會(huì)層面存在、變化和發(fā)展的根據(jù)。 用這種“旋轉(zhuǎn)著的中軸”研究社會(huì)問題，可以避免用同一種因素作為解釋各種社會(huì)層面存在、變化和發(fā)展根據(jù)的機(jī)械決定論。 2．?？率侨绾握撌鰴?quán)利和知識的關(guān)系的？　　 ?？轮饕獜囊韵氯齻€(gè)方面論述權(quán)力和知識的關(guān)系： 其一，知識是在權(quán)力的制約中形成與發(fā)展起來的，沒有脫離權(quán)力關(guān)系的抽象知識； 其二，權(quán)力離不開知識，不僅權(quán)力在特定的知識背景和知識結(jié)構(gòu)中形成，而且知識本身就是權(quán)力； 其三，權(quán)力同知識不可分，只有在權(quán)力與知識的聯(lián)系中才能把握權(quán)力的實(shí)質(zhì)與作用。 五、論述題（25分） 　　 1．哈貝馬斯如何論述目的理性行動(dòng)和交往行動(dòng)之間的關(guān)系？其實(shí)踐意義是什么？ 哈貝馬斯把社會(huì)行動(dòng)區(qū)分為兩大類：目的理性行動(dòng)和交往行動(dòng)，并指出兩類行動(dòng)具有不同的規(guī)范結(jié)構(gòu)。 目的理性行動(dòng)中的規(guī)范結(jié)構(gòu)展開于主觀與客觀之間，亦即展開于人與物之間，而交往行動(dòng)中的規(guī)范結(jié)構(gòu)則展開于主觀之間，亦即展開于人與人之間。 目的理性行動(dòng)把功利目標(biāo)、手段選擇、技術(shù)操作、價(jià)值測評和決策籌劃等因素考慮周全，并使這些因素在目的理性行動(dòng)中協(xié)調(diào)一致，這就是目的理性的規(guī)范結(jié)構(gòu)。 交往行動(dòng)的規(guī)范結(jié)構(gòu)要求人們在交往中按照真、誠、正、通四條原則行事（或根據(jù)交往理性行事），這也就是哈貝馬斯追求的交往行動(dòng)理性化。 哈貝馬斯觀點(diǎn)的實(shí)踐意義在于，在現(xiàn)實(shí)生活中，要把生產(chǎn)活動(dòng)、科學(xué)實(shí)驗(yàn)等面對客觀事物的行動(dòng)同面對人的交往活動(dòng)區(qū)分開，不能用對待物的原則或行為方式去對待人。 請您刪除一下內(nèi)容，O(∩_∩)O謝謝?。?！2016年中央電大期末復(fù)習(xí)考試小抄大全，電大期末考試必備小抄，電大考試必過小抄Acetylcholine is a neurotransmitter released from nerve endings (terminals) in both the peripheral and the central nervous systems. It is synthesized within the nerve terminal from choline, taken up from the tissue fluid into the nerve ending by a specialized transport mechanism. The enzyme necessary for this synthesis is formed in the nerve cell body and passes down the axon to its end, carried in the axoplasmic flow, the slow movement of intracellular substance (cytoplasm). Acetylcholine is stored in the nerve terminal, sequestered in small vesicles awaiting release. When a nerve action potential reaches and invades the nerve terminal, a shower of acetylcholine vesicles is released into the junction (synapse) between the nerve terminal and the ‘effector’ cell which the nerve activates. This may be another nerve cell or a muscle or gland cell. Thus electrical signals are converted to chemical signals, allowing messages to be passed between nerve cells or between nerve cells and non-nerve cells. This process is termed ‘chemical neurotransmission’ and was first demonstrated, for nerves to the heart, by the German pharmacologist Loewi in 1921. Chemical transmission involving acetylcholine is known as ‘cholinergic’. Acetylcholine acts as a transmitter between motor nerves and the fibres of skeletal muscle at all neuromuscular junctions. At this type of synapse, the nerve terminal is closely apposed to the cell membrane of a muscle fibre at the so-called motor end plate. On release, acetylcholine acts almost instantly, to cause a sequence of chemical and physical events (starting with depolarization of the motor endplate) which cause contraction of the muscle fibre. This is exactly what is required for voluntary muscles in which a rapid response to a command is required. The action of acetylcholine is terminated rapidly, in around 10 milliseconds; an enzyme (cholinesterase) breaks the transmitter down into choline and an acetate ion. The choline is then available for re-uptake into the nerve terminal. These same principles apply to cholinergic transmission at sites other than neuromuscular junctions, although the structure of the synapses differs. In the autonomic nervous system these include nerve-to-nerve synapses at the relay stations (ganglia) in both the sympathetic and the parasympathetic divisions, and the endings of parasympathetic nerve fibres on non-voluntary (smooth) muscle, the heart, and glandular cells; in response to activation of this nerve supply, smooth muscle contracts (notably in the gut), the frequency of heart beat is slowed, and glands secrete. Acetylcholine is also an important transmitter at many sites in the brain at nerve-to-nerve synapses. To understand how acetylcholine brings about a variety of effects in different cells it is necessary to understand membrane receptors. In post-synaptic membranes (those of the cells on which the nerve fibres terminate) there are many different sorts of receptors and some are receptors for acetylcholine. These are protein molecules that react specifically with acetylcholine in a reversible fashion. It is the complex of receptor combined with acetylcholine which brings about a biophysical reaction, resulting in the response from the receptive cell. Two major types of acetylcholine receptors exist in the membranes of cells. The type in skeletal muscle is known as ‘nicotinic’; in glands, smooth muscle, and the heart they are ‘muscarinic’; and there are some of each type in the brain. These terms are used because nicotine mimics the action of acetylcholine at nicotinic receptors, whereas muscarine, an alkaloid from the mushroom Amanita muscaria, mimics the action of acetylcholine at the muscarinic receptors. Acetylcholine is the neurotransmitter produced by neurons referred to as cholinergic neurons. In the peripheral nervous system acetylcholine plays a role in skeletal muscle movement, as well as in the regulation of smooth muscle and cardiac muscle. In the central nervous system acetylcholine is believed to be involved in learning, memory, and mood. Acetylcholine is synthesized from choline and acetyl coenzyme A through the action of the enzyme choline acetyltransferase and becomes packaged into membrane-boundvesicles. After the arrival of a nerve signal at the termination of an axon, the vesicles fuse with the cell membrane, causing the release of acetylcholine into thesynaptic cleft. For the nerve signal to continue, acetylcholine must diffuse to another nearby neuron or muscle cell, where it will bind and activate areceptorprotein. There are two main types of cholinergic receptors, nicotinic and muscarinic. Nicotinic receptors are located at synapses between two neurons and at synapses between neurons and skeletal muscle cells. Upon activation a nicotinic receptor acts as a channel for the movement of ions into and out of the neuron, directly resulting indepolarizationof the neuron. Muscarinic receptors, located at the synapses of nerves with smooth or cardiac muscle, trigger a chain of chemical events referred to as signal transduction. For a cholinergic neuron to receive another impulse, acetylcholine must be released from the receptor to which it has bound. This will only happen if the concentration of acetylcholine in the synaptic cleft is very low. Low synaptic concentrations of acetylcholine can be maintained via a hydrolysis reaction catalyzed by the enzyme acetylcholinesterase. This enzyme hydrolyzes acetylcholine into acetic acid and choline. If acetylcholinesterase activity is inhibited, the synaptic concentration of acetylcholine will remain higher than normal. If this inhibition is irreversible, as in the case of exposure to many nerve gases and some pesticides, sweating, bronchial constriction, convulsions, paralysis, and possibly death can occur. Although irreversible inhibition is dangerous, beneficial effects may be derived from transient (reversible) inhibition. Drugs that inhibit acetylcholinesterase in a reversible manner have been shown to improve memory in some people with Alzheimers disease. abstract expressionism, movement of abstract painting that emerged in New York City during the mid-1940s and attained singular prominence in American art in the following decade; also called action painting and the New York school. It was the first important school in American painting to declare its independence from European styles and to influence the development of art abroad. Arshile Gorky first gave impetus to the movement. His paintings, derived at first from the art of Picasso, Mir, and surrealism, became more personally expressive. Jackson Pollocks turbulent yet elegant abstract paintings, which were created by spattering paint on huge canvases placed on the floor, brought abstract expressionism before a hostile public. Willem de Koonings first one-man show in 1948 established him as a highly influential artist. His intensely complicated abstract paintings of the 1940s were followed by images of Woman, grotesque versions of buxom womanhood, which were virtually unparalleled in the sustained savagery of their execution. Painters such as Philip Guston and Franz Kline turned to the abstract late in the 1940s and soon developed strikingly original styles—the former, lyrical and evocative, the latter, forceful and boldly dramatic. Other important artists involved with the movement included Hans Hofmann, Robert Motherwell, and Mark Rothko; among other major abstract expressionists were such painters as Clyfford Still, Theodoros Stamos, Adolph Gottlieb, Helen Frankenthaler, Lee Krasner, and Esteban Vicente. Abstract expressionism presented a broad range of stylistic diversity within its largely, though not exclusively, nonrepresentational framework. For example, the expressive violence and activity in paintings by de Kooning or Pollock marked the opposite end of the pole from the simple, quiescent images of Mark Rothko. Basic to most abstract expressionist painting were the attention paid to surface qualities, i.e., qualities of brushstroke and texture; the use of huge canvases; the adoption of an approach to space in which all parts of the canvas played an equally vital role in the total work; the harnessing of accidents that occurred during the process of painting; the glorification of the act of painting itself as a means of visual communication; and the attempt to transfer pure emotion directly onto the canvas. The movement had an inestimable influence on the many varieties of work that followed it, especially in the way its proponents used color and materials. Its essential energy transmitted an enduring excitement to the American art scene. Science and technology is quite a broad category, and it covers everything from studying the stars and the planets to studying molecules and viruses. Beginning with the Greeks and Hipparchus, continuing through Ptolemy, Copernicus and Galileo, and today with our work on the International Space Station, man continues to learn more and more about the heavens. From here, we look inward to biochemistry and biology. To truly understand biochemistry, scientists study and see the unseen bystudying the chemistry of biological processes. This science, along with biophysics, aims to bring a better understanding of how bodies work – from how we turn food into energy to how nerve impulses transmit.analytic geometry, branch ofgeometryin which points are represented with respect to a coordinate system, such asCartesian coordinates, and in which the approach to geometric problems is primarily algebraic. Its most common application is in the representation of equations involving two or three variables as curves in two or three dimensions or surfaces in three dimensions. For example, the linear equationax+by+c=0 represents a straight line in thexy-plane, and the linear equationax+by+cz+d=0 represents a plane in space, wherea, b, c,anddare constant numbers (coefficients). In this way a geometric problem can be translated into an algebraic problem and the methods of algebra brought to bear on its solution. Conversely, the solution of a problem in algebra, such as finding the roots of an equation or system of equations, can be estimated or sometimes given exactly by geometric means, e.g., plotting curves and surfaces and determining points of intersection. In plane analytic geometry a line is frequently described in terms of its slope, which expresses its inclination to the coordinate axes; technically, the slopemof a straight line is the (trigonometric) tangent of the angle it makes with thex-axis. If the line is parallel to thex-axis, its slope is zero. Two or more lines with equal slopes are parallel to one another. In general, the slope of the line through the points (x1,y1) and (x2,y2) is given bym= (y2-y1) / (x2-x1). The conic sections are treated in analytic geometry as the curves corresponding to the general quadratic equationax2+bxy+cy2+dx+ey+f=0, wherea, b,?…?, fare constants anda, b,andcare not all zero. In solid analytic geometry the orientation of a straight line is given not by one slope but by its direction cosines, λ, μ, and ν, the cosines of the angles the line makes with thex-, y-,andz-axes, respectively; these satisfy the relationship λ2+μ2+ν2= 1. In the same way that the conic sections are studied in two dimensions, the 17 quadric surfaces, e.g., the ellipsoid, paraboloid, and elliptic paraboloid, are studied in solid analytic geometry in terms of the general equationax2+by2+cz2+dxy+exz+fyz+px+qy+rz+s=0. The methods of analytic geometry have been generalized to four or more dimensions and have been combined with other branches of geometry. Analytic geometry was introduced by RenDescartesin 1637 and was of fundamental importance in the development of thecalculusby Sir Isaac Newton and G. W. Leibniz in the late 17th cent. More recently it has served as the basis for the modern development and exploitation ofalgebraic geometry. circle, closed plane curve consisting of all points at a given distance from some fixed point, called the center. A circle is a conic section cut by a plane perpendicular to the axis of the cone. The term circle is also used to refer to the region enclosed by the curve, more properly called a circular region. The radius of a circle is any line segment connecting the center and a point on the curve; the term is also used for the length r of this segment, i.e., the common distance of all points on the curve from the center. Similarly, the circumference of a circle is either the curve itself or its length of arc. A line segment whose two ends lie on the circumference is a chord; a chord through the center is the diameter. A secant is a line of indefinite length intersecting the circle at two points, the segment of it within the circle being a chord. A tangent to a circle is a straight line touching the circle at only one point, the point of contact, or tangency, and is always perpendicular to the radius drawn to this point. A circle is inscribed in a polygon if each side of the polygon is tangent to the circle; a circle is circumscribed about a polygon if all the vertices of the polygon lie on the circumference. The length of the circumference C of a circle is equal to π (see pi) times twice the radius distance r, or C=2πr. The area A bounded by a circle is given by A=πr2. Greek geometry left many unsolved problems about circles, including the problem of squaring the circle, i.e., constructing a square with an area equal to that of a given circle, using only a straight edge and compass; it was finally proved impossible in the late 19th cent. (see geometric problems of antiquity). In modern mathematics the circle is the basis for such theories as inversive geometry and certain non-Euclidean geometries. The circle figures significantly in many cultures. In religion and art it