★英語聽力頻道為大家整理的初中英語聽力訓(xùn)練mp3：短嘴鱷可以再長牙齒，供大家參考。更多閱讀請查看本站英語聽力頻道。
Fun Fact: Alligators Can Regrow Teeth
有趣的事實(shí)：短嘴鱷可以再長牙齒
Fun fact about alligators: they can regrow any of their eighty teeth up to fifty times. Which is pretty impressive, especially compared to us relatively dentally challenged humans: when we lose adult teeth, there’s no regrowing them.
關(guān)于短嘴鱷的有趣的事實(shí)：它們的八十顆牙齒中任一一顆牙都可以重新生長五十次。這實(shí)在讓人驚訝，特別是和我們?nèi)祟愌例X的相對障礙相比：當(dāng)我們失去恒牙便再無重生的可能。
Regrowing Teeth
牙齒再生
But that may change. Hoping to save the toothless among us from being fated to wearing dentures, scientists are studying how alligators regrow teeth and how the same process may be able to work in humans.
但這樣的情況可能有所改觀。為了擺脫我們因沒有牙齒而戴上假牙的命運(yùn)，科學(xué)家們正在研究短嘴鱷牙齒再生的機(jī)理以及同樣的方式如何能夠同樣作用于人類。
Using X rays and tissue samples, plus lab grown gator tooth cells and computer models, scientists have learned that for each gator tooth there are two tooth precursors, both of which are triggered to grow when a mature tooth is lost.
利用X射線和組織樣本，加上實(shí)驗(yàn)室生長的鱷魚牙齒細(xì)胞和計(jì)算機(jī)模型，科學(xué)家發(fā)現(xiàn)每一顆鱷魚牙齒上均有兩個(gè)牙前體細(xì)胞，當(dāng)成熟的牙齒脫落，這兩個(gè)前體就會觸發(fā)新牙生長。
The growth process begins when a band of tissue called the dental lamina begins to bulge. This wakes up stem cells and signaling molecules that kick start new tooth growth. And finally a new tooth grows in to replace the one that was lost.
當(dāng)一組名為牙板的組織開始膨脹，再生的過程就開始了。這一過程喚醒了干細(xì)胞和推動(dòng)新牙生長的信號分子。最后一顆新牙長出并取代原先那顆失去的牙。
Evolution
進(jìn)化
Now, it’s difficult to take what nature and evolution have combined to create in one species and somehow make it happen in another. But we humans do have remnants of dental lamina. And scientists are trying to figure out how to manipulate it to enable tooth growth in people similar to how it works in alligators. We could potentially use that same knowledge to turn off the processes in humans that sometimes cause problems like growing too many teeth or oddly shaped and spaced teeth.
現(xiàn)在的問題在于，如何讓這個(gè)在一個(gè)物種上結(jié)合了自然和進(jìn)化的產(chǎn)物發(fā)生在另一物種身上。但我們?nèi)祟惾匀挥袣埩舻难腊?。科學(xué)家們正試圖找出如何操作的方法，使人類牙齒生長的機(jī)理和短嘴鱷的相似。我們很可能利用相同的知識結(jié)束人類牙齒生長時(shí)常產(chǎn)生的問題的過程，例如長了多余的牙齒，或者齙牙以及間隙牙。
The alligator research is still in the early stages, so regrowing human teeth is still a ways away. But before too long, replacing a lost adult tooth may be as simple as growing it back.
短嘴鱷的研究仍然處于早期階段，因此人類離牙齒再生的現(xiàn)實(shí)還有一定距離。但不久的將來，也許替換一顆掉落的恒牙和新長一顆一樣簡單。
Fun Fact: Alligators Can Regrow Teeth
有趣的事實(shí)：短嘴鱷可以再長牙齒
Fun fact about alligators: they can regrow any of their eighty teeth up to fifty times. Which is pretty impressive, especially compared to us relatively dentally challenged humans: when we lose adult teeth, there’s no regrowing them.
關(guān)于短嘴鱷的有趣的事實(shí)：它們的八十顆牙齒中任一一顆牙都可以重新生長五十次。這實(shí)在讓人驚訝，特別是和我們?nèi)祟愌例X的相對障礙相比：當(dāng)我們失去恒牙便再無重生的可能。
Regrowing Teeth
牙齒再生
But that may change. Hoping to save the toothless among us from being fated to wearing dentures, scientists are studying how alligators regrow teeth and how the same process may be able to work in humans.
但這樣的情況可能有所改觀。為了擺脫我們因沒有牙齒而戴上假牙的命運(yùn)，科學(xué)家們正在研究短嘴鱷牙齒再生的機(jī)理以及同樣的方式如何能夠同樣作用于人類。
Using X rays and tissue samples, plus lab grown gator tooth cells and computer models, scientists have learned that for each gator tooth there are two tooth precursors, both of which are triggered to grow when a mature tooth is lost.
利用X射線和組織樣本，加上實(shí)驗(yàn)室生長的鱷魚牙齒細(xì)胞和計(jì)算機(jī)模型，科學(xué)家發(fā)現(xiàn)每一顆鱷魚牙齒上均有兩個(gè)牙前體細(xì)胞，當(dāng)成熟的牙齒脫落，這兩個(gè)前體就會觸發(fā)新牙生長。
The growth process begins when a band of tissue called the dental lamina begins to bulge. This wakes up stem cells and signaling molecules that kick start new tooth growth. And finally a new tooth grows in to replace the one that was lost.
當(dāng)一組名為牙板的組織開始膨脹，再生的過程就開始了。這一過程喚醒了干細(xì)胞和推動(dòng)新牙生長的信號分子。最后一顆新牙長出并取代原先那顆失去的牙。
Evolution
進(jìn)化
Now, it’s difficult to take what nature and evolution have combined to create in one species and somehow make it happen in another. But we humans do have remnants of dental lamina. And scientists are trying to figure out how to manipulate it to enable tooth growth in people similar to how it works in alligators. We could potentially use that same knowledge to turn off the processes in humans that sometimes cause problems like growing too many teeth or oddly shaped and spaced teeth.
現(xiàn)在的問題在于，如何讓這個(gè)在一個(gè)物種上結(jié)合了自然和進(jìn)化的產(chǎn)物發(fā)生在另一物種身上。但我們?nèi)祟惾匀挥袣埩舻难腊?。科學(xué)家們正試圖找出如何操作的方法，使人類牙齒生長的機(jī)理和短嘴鱷的相似。我們很可能利用相同的知識結(jié)束人類牙齒生長時(shí)常產(chǎn)生的問題的過程，例如長了多余的牙齒，或者齙牙以及間隙牙。
The alligator research is still in the early stages, so regrowing human teeth is still a ways away. But before too long, replacing a lost adult tooth may be as simple as growing it back.
短嘴鱷的研究仍然處于早期階段，因此人類離牙齒再生的現(xiàn)實(shí)還有一定距離。但不久的將來，也許替換一顆掉落的恒牙和新長一顆一樣簡單。