蔓藤植物纏繞樹干或者格架是很常見的現(xiàn)象,但是你是否曾經(jīng)想過他們是怎么做到的呢?



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選材/校對/翻譯:hqj5715
The purpose of the twining is to anchor the vine, and in some cases the vines themselves do the twining, while in others the vines have small appendages called tendrils that coil around twigs or trellises. How does the vine know to twine, and in what direction? The fact is the vine doesn't know anything; its coiling is a blind reaction, so to speak, caused by chemical changes inside it. The vine twines because the cells on one side grow faster than the cells on the opposite side. When the growing tip of the vine touches an obstacle, such as a twig, this stimulates the cells of the vine on the side opposite the twig to grow faster than those next to the twig. As the side of the vine opposite the twig gets longer, and the side touching the twig grows very little, the vine is pushed around the twig. Most vines are not particular about which way they twine. If the outside of the vine’s tip touches an obstacle the vine will change direction.
纏繞的目的是用于固定蔓藤,有部分蔓藤自己也進行纏繞,而另外一些蔓藤具有一些稱作卷須的小的附屬物,這些附屬物能纏繞枝干或者格架。 蔓藤植物是怎樣知道去纏繞、以什么方向去纏繞的呢?事實上是蔓藤植物什么也不知道,他們所進行的纏繞只是一種盲目的行為,也就是所謂的通過他們體內(nèi)的化學改變。 滿滕植物纏繞的原因是一側(cè)細胞生長的速度比對側(cè)細胞生長的速度快。當蔓藤正在生長的尖端碰到一障礙物,比如一個枝干,便刺激蔓藤對著枝干一邊的的細胞快速生長,超過靠近枝干一邊細胞的速度。 當蔓藤對著枝干的一邊變長,而觸碰到枝干的一邊生長非常緩慢,蔓藤便沿著枝干推進。大部分的蔓藤植物并沒有特定纏繞的方向。如果蔓藤外側(cè)的一邊尖端碰到障礙物時,蔓藤便會干煸方向。