託福聽力經典加試梯目:神經元細胞
神經元細胞
lecture神經膠質細胞研究。教授說早期對人類大腦的研究集中在神經細胞neuron,讓一男生起來回答上節課的主要内容,男生說生物電生物電bioelectricity 通過神經細胞傳導,通過兩個神經細胞的接觸點傳到下一個細胞,有趣的是。。說到這裏被教授打斷,說他答得已經很完整瞭(有題,問教授打斷他的用意)。神經膠質細胞glial cells的作用在早期被忽視瞭,人們認爲膠質細胞隻有支持神經細胞的作用。後來人們發現膠質細胞也有傳導信息的作用,不是通過生物電,而是化學物質傳導。於是總共有三種傳導方式,神經細胞間,膠質細胞間,神經和膠質細胞互相傳導。而且發現膠質細胞的數量及其鉅大,遠多於神經細胞。同時還可能有修複神經細胞,決定哪些神經長的大[記得可能不準]。教授又說,膠質細胞可能與智力有關,越多智商越髙,但這不確定。教授說對膠質細胞的研究是一個很open up的領域,建議學生們可以考慮畢業後作深入研究(有題)。
重要:biology 講glial cell。以往人們對神經傳導的研究僅限於neuron(神經元),也叫nervecell。神經傳導通過electrical communication從一個結點傳到另一個結點,神經元被認爲起主要作用,glial cell研究的很少,一直被忽略,被看作help the growth of neurons
(出題),起輔力作用。後來偶然發現大腦中glial cell比neuron的數目多很多,glial cell引起瞭科學傢的重視,開始研究它究竟起什麽作用(此處出題,問glialcell怎麽引起科學傢註意的)。後來有一重大突破,
發現glial cell傳導信號不是用的electricalsignal,而是用chemical conductor(一說chemical communication)(此處出題)。傳統觀點一直誤以爲glial cell也像nervecell一樣用電信號。後來談到glial cell可能的作用:使人更intelligent。對glial cell的認識目前十分有限,但相關研究已經開始流行,是大傢畢業之後可選的研究課題(此處出題)
Glial cell isthought to help the growth of neurons. However, scientists accidentallydiscover that glial’s amount is much more than the neuron. So glial attractpeople’s attention. They use chemical conductor to communicate with others. Soglial to neuron, g to n, g to g, n to n are all available. In the past glialwas thought to support nerve cell.
Glial cells (神經膠質細胞)and Neurons (神經細胞)
Glial cells,commonly called neuroglia or simply glia, are non-neuronal cellsthat provide support and nutrition, maintainhomeostasis,form myelin,and participate in signal transmission in the nervoussystem. In the human brain, glia are estimated to outnumberneurons by about 10 to 1.[1]
Glial cellsprovide support and protection for neurons, the other main type of cell in the central nervoussystem. They are thus known as the "glue"膠水 of the nervous system. The four main functions ofglial cells are to surround neurons and hold them in place固定, to supply nutrientsand oxygento neurons供養, to insulate one neuron from another隔開, and to destroypathogensand remove dead neurons破壞病菌,轉移死N.
Glia wasdiscovered in 1856by the pathologist Rudolf Virchow in his search for a 'connectivetissue' in the brain大腦的連接組織.The human brain contains about ten timesmore glial cells than neurons. [1]Following its discovery in the late 19th century, this fact underwentsignificant media distortion, emerging as the famous myth claiming that"we are using only 10% of our brain". The role of glial cells asmanagers of communications in the synapse突觸 gap,thus modifying learning pace, has been discovered only very recently
In addition toneurons, the nervous system is populated with another category of cells, glialcells. Glial cells are approximately 10 times more plentiful than neurons, butsince they are approximately one-tenth the size, they take up equal size, gliais a Greek term meaning glue, researches originally believed that glial cellsserved as the putty that held the neurons together, recent research indicatesthat these cells provide very important contributions.
a neuron is thefunctioning unit of the nervous system, specialized to receive, integrate, andtransmit information, the flow of information moves in the following direction.
託福聽力加試梯的位置不固定,考生很難分辨哪一道是加試梯,隻能通過日常積累來判斷。大傢盡量不要憑空揣測,以免影響自己的託福成績。
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