蔓藤植物缠绕树干或者格架是很常见的现象，但是你是否曾经想过他们是怎么做到的呢？



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选材／校对／翻译：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.
缠绕的目的是用于固定蔓藤，有部分蔓藤自己也进行缠绕，而另外一些蔓藤具有一些称作卷须的小的附属物，这些附属物能缠绕枝干或者格架。 蔓藤植物是怎样知道去缠绕、以什么方向去缠绕的呢？事实上是蔓藤植物什么也不知道，他们所进行的缠绕只是一种盲目的行为，也就是所谓的通过他们体内的化学改变。 满滕植物缠绕的原因是一侧细胞生长的速度比对侧细胞生长的速度快。当蔓藤正在生长的尖端碰到一障碍物，比如一个枝干，便刺激蔓藤对着枝干一边的的细胞快速生长，超过靠近枝干一边细胞的速度。 当蔓藤对着枝干的一边变长，而触碰到枝干的一边生长非常缓慢，蔓藤便沿着枝干推进。大部分的蔓藤植物并没有特定缠绕的方向。如果蔓藤外侧的一边尖端碰到障碍物时，蔓藤便会干煸方向。