托福聽力經(jīng)典加試梯目:神經(jīng)元細胞
神經(jīng)元細胞
lecture神經(jīng)膠質(zhì)細胞研究。教授說早期對人類大腦的研究集中在神經(jīng)細胞neuron，讓一男生起來回答上節(jié)課的主要內(nèi)容，男生說生物電生物電bioelectricity 通過神經(jīng)細胞傳導(dǎo)，通過兩個神經(jīng)細胞的接觸點傳到下一個細胞，有趣的是。。說到這里被教授打斷，說他答得已經(jīng)很完整了(有題，問教授打斷他的用意)。神經(jīng)膠質(zhì)細胞glial cells的作用在早期被忽視了，人們認為膠質(zhì)細胞只有支持神經(jīng)細胞的作用。后來人們發(fā)現(xiàn)膠質(zhì)細胞也有傳導(dǎo)信息的作用，不是通過生物電，而是化學物質(zhì)傳導(dǎo)。于是總共有三種傳導(dǎo)方式，神經(jīng)細胞間，膠質(zhì)細胞間，神經(jīng)和膠質(zhì)細胞互相傳導(dǎo)。而且發(fā)現(xiàn)膠質(zhì)細胞的數(shù)量及其巨大，遠多于神經(jīng)細胞。同時還可能有修復(fù)神經(jīng)細胞，決定哪些神經(jīng)長的大[記得可能不準]。教授又說，膠質(zhì)細胞可能與智力有關(guān)，越多智商越高，但這不確定。教授說對膠質(zhì)細胞的研究是一個很open up的領(lǐng)域，建議學生們可以考慮畢業(yè)后作深入研究(有題)。
重要：biology 講glial cell。以往人們對神經(jīng)傳導(dǎo)的研究僅限于neuron(神經(jīng)元)，也叫nervecell。神經(jīng)傳導(dǎo)通過electrical communication從一個結(jié)點傳到另一個結(jié)點，神經(jīng)元被認為起主要作用，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。后來偶然發(fā)現(xiàn)大腦中g(shù)lial cell比neuron的數(shù)目多很多，glial cell引起了科學家的重視，開始研究它究竟起什么作用(此處出題，問glialcell怎么引起科學家注意的)。后來有一重大突破，
發(fā)現(xiàn)glial cell傳導(dǎo)信號不是用的electricalsignal，而是用chemical conductor(一說chemical communication)(此處出題)。傳統(tǒng)觀點一直誤以為glial cell也像nervecell一樣用電信號。后來談到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(guān)研究已經(jīng)開始流行，是大家畢業(yè)之后可選的研究課題(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(jīng)膠質(zhì)細胞)and Neurons (神經(jīng)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(yǎng), to insulate one neuron from another隔開, and to destroypathogensand remove dead neurons破壞病菌，轉(zhuǎn)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.
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