時(shí)差N小時(shí): 嘿!你傷到我的樹葉了!
唐：雅艾爾，上次我修理草坪的時(shí)候忍不住想，那些樹木花草感覺(jué)不到疼痛是很幸運(yùn)的。
Yael: Ture,Don. But did you know that scientistshave discovered that plants use a form of electricalsignaling that spreads throughout the plant whenone of its leaves is injured.
雅艾爾：的確，唐。但你知道嗎，科學(xué)家們發(fā)現(xiàn)有一種植物，一旦其樹葉受傷，會(huì)立馬向全身傳導(dǎo)一種電子信號(hào)。
Don：Like the electric signals that spread through our nerves when we are injured?
唐：就像人類受傷后通過(guò)神經(jīng)傳導(dǎo)的電信號(hào)嗎?
Yael: The electric signals in plants, called “system potentials”, are not exactly like the electric“action potentials” in the nervous systems of animals. But they do have certain similarities.Both kinds of electric signals travel very quickly from the site of the wound to distant parts ofthe organism.
雅艾爾：植物體內(nèi)的電信號(hào)被稱為“系統(tǒng)電位”，它與動(dòng)物神經(jīng)系統(tǒng)里的“動(dòng)作電位”并不完全一樣。不過(guò)它們的確有某些相似之處。這兩種電信號(hào)都能很快地從受傷的部位傳到生物遠(yuǎn)處的部位。
Don：Cool.
唐：酷。
Yael: The way these electric signals were discovered is pretty cool,too. A team of Germanscientists carefully inserted super thin, hair like electrodes through open stomata on the leaves.Stomata are tiny pores, found on the undersides of leaves, that open and close to controlevaporation and gas exchange for the plant. The tiny electrodes could then record activityfrom cells inside the leaf. Using these sensitive electrodes, the scientists were able to recordchanges in voltage as the electric signals spread from leaf to leaf across the entire plant. Thesystem potentials in plants move much more slowly than the electric signals that run throughour neurons, spreading at rates between two to four inches per minute.
雅艾爾：發(fā)現(xiàn)這種電子信號(hào)的方式也相當(dāng)酷。一個(gè)德國(guó)的科學(xué)家團(tuán)隊(duì)通過(guò)葉子張開的氣孔，仔細(xì)地植入了超薄、類似頭發(fā)的電極。氣孔是位于葉子下側(cè)的微小毛孔，這些氣孔的開放和關(guān)閉控制著植物水分的蒸騰和氣體交換。這些小電極能記錄葉片內(nèi)細(xì)胞的活動(dòng)。利用這些敏感電極，科學(xué)家能夠記錄電信號(hào)從一片葉子傳到另一片葉子時(shí)電壓的改變。植物體內(nèi)的系統(tǒng)電位比在人體神經(jīng)系統(tǒng)內(nèi)流動(dòng)的電信號(hào)要慢得多。人體內(nèi)電信號(hào)傳導(dǎo)速度為每分鐘二至四英寸。
Don：So,can my grass feel pain?
唐：那么，草能感覺(jué)到疼痛嗎?
Yael: No. Plants don't have brains or feelings the way animals do. But it is important for plantsto detect damage from herbivores, insects or even lawnmowers. Electrical signaling is one wayplants know there is damage and it's time to activate defense mechanisms or begin re growthin damaged areas.
雅艾爾：不能，植物并沒(méi)有大腦，不能像動(dòng)物一樣有感覺(jué)。但是對(duì)植物來(lái)說(shuō)，探測(cè)來(lái)自食草動(dòng)物、昆蟲甚至剪草機(jī)的傷害非常重要。電子信號(hào)是植物用來(lái)感知受傷部位，并抓緊時(shí)間激活防御機(jī)制，或修復(fù)受傷部位的方法。
