Placeholder Image

字幕列表 影片播放

已審核 字幕已審核
  • To us humans, aging seems inevitable - probably because no human has ever not aged. But getting

    對人類而言,老化似乎是必然的- 或許是因為沒有人是不會老的 。但是

  • older isn’t as universal a fact of life as we might think.

    老化並不如我們想像中是個放睹四海皆準的事實。

  • Take the naked mole rat. Unlike their less-naked brethren, they don’t appear to age after

    以裸鼴鼠為例子。 跟牠們有毛的同類們不一樣,牠們成年後不會隨著

  • reaching adulthood - years pass, but the rats don’t get weaker, more susceptible to disease,

    時間老化-時間過去,但這些老鼠不會變虚弱,不受疾病侵擾,

  • or wrinkly...at least not any more wrinkly...and they keep on making as many babies as ever.

    皮膚也不會長皺紋...至少不會長更多皺紋...而且牠們一如往常不停繁衍下一代。

  • Surprisingly, they aren’t any more likely to die in old age than when theyre young

    更令人驚訝的是,裸鼴鼠不會因為年紀愈來愈老就比牠們在年輕時更容易死忙。

  • adults. It’s as if theyve found the fountain of youth, though perhaps not the fountain

    就好像他們找到青春之泉,但也許不是美麗之泉

  • of beauty. And naked mole rats aren’t alone in not aging: rockfish, lobsters, and bristlecone

    在不老方面,裸鼴鼠並不孤单 石斑魚,龍蝦, 及狐尾松

  • pines also seem to stay forever young...or at least forever middle-aged.

    也以乎永遠年輕...或至少永遠是中年。

  • Were not exactly sure how these species do it, but their anti-aging secret may have

    我們不太確定這些物種是怎麼辦到的, 但是牠們抗衰老的秘密可能

  • to do with their ability to rebuild the DNA caps on their chromosomes. These caps, called

    和重建DNA保護套在染色體上的功能有關。這些保護套,叫做

  • telomeres, are one line of defense against aging in many species. That’s because cells

    端粒,是許多物種的一種抵禦衰老的方法。這是因為細胞

  • need to divide to replace old or dysfunctional cells, but each time they replicate, they

    為了取代舊的或無功能的細胞而分裂, 但每次細胞複製,

  • lose a little bit of DNA from the end of each chromosome. Normally that doesn’t matter,

    會從染色體失去一點DNA 。那通常不重要,

  • since these lost bits come from the telomere end caps that don’t encode important information.

    因為這些失去的部分是從不會編碼資訊的端粒的保護套。

  • But after many replications, the telomeres get trimmed so short that the cells can’t

    但經過多次複製會簡短端粒到細胞

  • afford to lose any more DNA, and they stop replicating.

    無法負荷失去更多DNA, 就停止複製。

  • Age-defying species like naked mole rats, however, pump out high levels of a telomere-rebuilding

    然而,抗衰老種類如裸鼴鼠,生產高度的重建端粒酶

  • enzyme that enables them to keep on replacing old and dysfunctional cells indefinitely.

    持續地取代舊的和不正常的細胞。

  • A few kinds of human cells make this enzyme, but the vast majority don’t. And even if

    少数人體細胞能制造这種酶,但絕大多數不能。即使

  • we could trick the rest into producing it, then we’d have another problem: more replications

    我們能誘導其餘的细胞制造酶,接著我們會有其它麻煩:更多的重複

  • means more chances for mutations that could turn a cell cancerous unlimited replication

    意味著更多機會突變會促使細胞癌變無限複製

  • increases a cell’s chances of becoming cancerous. Naked mole rats don’t care because they

    增加细胞變成癌細胞的機會。 裸鼴鼠不在乎,因為他們

  • seem to be immune to cancer; but we humans certainly aren’t.

    似乎對癌症免疫; 但我們人類肯定不是。

  • However, as amazing as naked mole rats are, they can only pause their agingthe tiny

    然而,就算裸鼴鼠如此令人驚歎,他們也只能暫停老化- 小小的

  • jellyfish Turritopsis dohrnii can age in reverse. Like butterflies, Turritopsis morph through

    燈塔水母卻可以逆轉年齡。就像蝴蝶一樣,燈塔水母

  • multiple stages during their life cycle. But unlike butterflies, if Turritopsis get wounded

    在其生命週期中通過許多階段。但跟蝴蝶不同的是,如果燈塔水母受傷

  • or if times get tough, they can morph backwards, reverting to their immature polyp form until

    或者生存環境變得艱困,牠們可以逆轉變身,回到牠們的不成熟息肉形態,直到

  • conditions improve. Theyre like, real life phoenixes.

    情況好轉。牠們就像,現實生活中的鳳凰。

  • However if humans could somehow imitate Turritopsistrick, it might not give us the kind of eternal

    但是,如果人在某種程度上能夠模仿燈塔水母的技能,它也許不會帶來那種我們

  • youth we’d be looking forfor one thing, melting into an amorphous blob where our cells

    一直追尋的青春...首先,融化成一種沒有固定形狀的一團

  • are reorganized and reprogrammed with new functions would not only be a mess; it would

    我們的細胞在其中重整和改組新功能,簡直不只是一團遭;

  • likely turn our brain cells into skin or muscle cells - and vice versa - erasing our memories

    那將會把我們的腦細胞變成皮膚或肌肉細胞- 反之亦然- 刪除我們的記憶

  • and our sense of self. And no matter what, eternal youth wouldn’t

    及我們的自我意識。而無論如何,永恆的青春不會

  • make us invincible - in fact, the longer a creature lives, the more time it has to get

    使我們立於不敗之地- 事實上,生物活得愈久,牠就必須經歷更久的

  • chomped, starved, or smooshed. So eventually, every naked mole rat, pine tree, and jellyfish

    咀嚼,挨餓,或壓擠。所以到最終,即使是裸鼴鼠,狐尾松和水母

  • will ultimately meet its end - because it’s possible to be immune to aging, but not to death.

    也要面對終點,因為可能可以避免老化,但無法避免死亡。

To us humans, aging seems inevitable - probably because no human has ever not aged. But getting

對人類而言,老化似乎是必然的- 或許是因為沒有人是不會老的 。但是

字幕與單字
已審核 字幕已審核

影片操作 你可以在這邊進行「影片」的調整,以及「字幕」的顯示

B2 中高級 中文 美國腔 細胞 水母 老化 燈塔 端粒 衰老

我們必須變老和死嗎? (Do We Have to Get Old and Die?)

  • 20748 783
    Charlene Tai 發佈於 2015 年 07 月 20 日
影片單字