未登录,请登录后再发表信息
最新评论 (0)
播放视频

植物保护自身的神奇方式

The amazing ways plants defend themselves - Valentin Hammoudi

你知道TED-Ed在举办涂色比赛么
本期节目最后会有更多详情 不要离开哦
这是棵番茄
This is a tomato plant,
这是个蚜虫 正吮吸着番茄叶子内的汁液
and this is an aphid, slowly killing the tomato plant
一点点消耗着番茄的生命
by sucking the juice out of its leaves.
番茄也产生了抵抗 它使用了物理化学防护手段
The tomato is putting up a fight, using both physical and chemical defenses
来驱逐这些来犯的昆虫
to repel the attacking insects.
但这不是全部
But that’s not all.
番茄也同时释放了化合物
The tomato is also releasing compounds
这些物质能促使附近番茄植株各自释放驱虫剂
that signal nearby tomato plants to release their own insect repellent.
植物经常受到攻击
Plants are constantly under attack.
它们面临的威胁小到微小的真菌细菌
They face threats ranging from microscopic fungi and bacteria,
小型食草类 如蚜虫 毛毛虫 蚂蚱
small herbivores, like aphids, caterpillars, and grasshoppers,
大到大型食草类 如陆龟 考拉 甚至大象
up to large herbivores, like tortoises, koalas, and elephants.
这些动物都想摄食植物获取
All are looking to devour plants to access the plentiful nutrients
获取植物叶 茎 果 根中大量的养分和水分
and water in their leaves, stems, fruits, and seeds.
但植物一系列的内外抵御措施也时刻准备着
But plants are ready with a whole series of internal and external defenses,
这就让植物自身成为不那么吸引人的晚餐
that make them a much less appealing meal,
甚至是致命的晚餐
or even a deadly one.
植物的抵御起始于其表面
Plants’ defenses start at their surface.
覆盖有树皮的树干是由木质素构成的
The bark covering tree trunks is full of lignin,
这是种难以咀嚼的化合物网络
a rigid web of compounds that’s tough to chew
而且不容易被病原菌渗透
and highly impermeable to pathogens.
树叶表面覆盖一层蜡质层保护膜
Leaves are protected by a waxy cuticle
可以阻挡昆虫和微生物
that deters insects and microbes.
一些植物更进一步
Some plants go a step further
有着能刺痛人的结构 来警示潜在的捕食者
with painful structures to warn would-be predators.
棘 脊 刺 结构能够抵御较大的草食类动物
Thorns, spines, and prickles discourage bigger herbivores.
为了对付小型昆虫
To deal with smaller pests,
一些植物的叶子有着锋利的毛状结构–毛状体
some plants’ leaves have sharp hair-like structures called trichomes.
四季豆长有小钩子可以刺穿臭虫和其他昆虫的腿
The kidney bean plant sports tiny hooks to stab the feet of bed bugs and other insects.
某些种类 毛状体 也可以产生化学刺激物
In some species, trichomes also dispense chemical irritants.
刺荨麻会释放组胺和其它毒素
Stinging nettles release a mixture of histamine and other toxins
如果接触到就会产生疼痛感及引发炎症
that cause pain and inflammation when touched.
对其他植物而言
For other plant species,
当草食动物咬下一口后就会产生痛感
the pain comes after an herbivore’s first bite.
菠菜 猕猴桃 菠萝 倒挂金钟 大黄
Spinach, kiwi fruit, pineapple, fuchsia and rhubarb,
都可以产生微小的针状结晶–针晶体
all produce microscopic, needle-shaped crystals called raphides.
它们可以造成动物嘴内侧产生小创口
They can cause tiny wounds in the inside of animals’ mouths,
这些小创口就提供了毒素进入体内的入口
which create entry points for toxins.
含羞草具有一种专门防止不被啃咬的特殊策略
The mimosa plant has a strategy designed to prevent herbivores from taking a bite at all.
特化的机械感受器细胞能感受到触碰
Specialized mechanoreceptor cells detect touch
并发射电信号 电信号从小叶片直达基部
and shoot an electrical signal through the leaflet to its base,
导致那里的细胞释放带电粒子
causing cells there to release charged particles.
带电量的增强会导致细胞脱水
The buildup of charge draws water out of these cells,
因此植物会枯萎 将叶片收缩闭合
and they shrivel, pulling the leaflet closed.
这种折叠叶片的行动会将昆虫吓跑
The folding movement scares insects away,
蔫了的叶子看上去对大型动物也不是很可口
and the shrunken leaves look less appealing to larger animals.
如果这些外在抵御措施土崩瓦解
If these external defenses are breached,
植物的免疫系统就会起作用
the plant immune system springs into action.
植物不像动物一样有分开的免疫系统
Plants don’t have a separate immune system like animals.
而是每个细胞都有探知并抵御入侵者的能力
Instead, every cell has the ability to detect and defend against invaders.
特化的感受器可以识别某些分子
Specialized receptors can recognize molecules
这些分子可以感知到危险微生物或是昆虫的存在
that signal the presence of dangerous microbes or insects.
作为回应 免疫系统会激发一连串抵御手段
In response, the immune system initiates a battery of defensive maneuvers.
为了阻止更多病原菌进入体内
To prevent more pathogens from making their way inside,
蜡质层会变厚 细胞壁会变坚韧
the waxy cuticle thickens and cell walls get stronger.
保卫细胞将叶片气孔围住
Guard cells seal up pores in the leaves.
如果微生物吞食植物的某一部分
And if microbes are devouring one section of the plant,
这些细胞就会自我销毁 隔离感染
those cells can self-destruct to quarantine the infection.
同时也会产生对微生物和昆虫有毒性的化合物
Compounds toxic to microbes and insects are also produced,
通常都是专一应对特定威胁的化合物
often tailor-made for a specific threat.
被人类用作毒品药物及调料的许多植物分子
Many of the plant molecules that humans have adopted as drugs, medicines and seasonings
都是作为植物免疫系统的一部分而进化来的
evolved as part of plants’ immune systems
因为它们要么抗菌 要么杀虫
because they’re antimicrobial, or insecticidal.
植物的一部分遭到攻击会通过激素
An area of a plant under attack can alert other regions using hormones,
风传化合物 甚至电子信号示警植物的其他部分
airborne compounds, or even electrical signals.
当植物其他部分感知到这些信号
When other parts of the plant detect these signals,
它们会加快防御性化合物的生成
they ramp up production of defensive compounds.
对于某些生物 如番茄
And for some species, like tomatoes,
这种早期预警系统还能够示警周围相邻植物
this early warning system also alerts their neighbors.
一些植物甚至可以招募盟友
Some plants can even recruit allies
采取一种更强大的抵御方式应对潜在的攻击者
to adopt a strong offense against their would-be attackers.
当棉花受到毛毛虫的围攻
Cotton plants under siege by caterpillars,
就会释放10到12种化学物的混合体到空气中
release a specific cocktail of ten to twelve chemicals into the air.
这些混合体吸引来寄生蜂 在毛毛虫体内产卵
This mixture attracts parasitic wasps that lay eggs inside the caterpillars.
植物或许不能逃离攻击现场
Plants may not be able to flee the scene of an attack,
也不能用尖牙利爪打退捕食者
or fight off predators with teeth and claws,
但拥有了坚固的盔甲 弹药充满化学武器库
but with sturdy armor, a well-stocked chemical arsenal,
近邻的站岗放哨 跨物种的强强联盟
a neighborhood watch, and cross-species alliances,
植物也不总是一顿唾手可得的美餐
a plant isn’t always an easy meal.
你知道TED-Ed在举办涂色大赛么
每月 我们会从受欢迎的TED动画片中挑选片段
Once a month, we take selected scenes from your favorite TED animations,
认真清除掉原始涂色
and we careful remove their original coloring.
之后我们会邀请TED-Ed的观众们
We then invite the TED-Ed community to
参与友好的涂色大赛 来给插图重新涂色
recolor the illustrations in a friendly coloring competition,
这次大赛由众筹举办
hosted on our Patreon on page.
如果你想参加
If you are a participant,
就把你的好作品发给我们
send us your best work,
或许就能在我们的社交媒体频道看到
and you might see it feathered on our social media channels
当然是在以后的 TED-Ed 视频中啦
in future TED-Ed videos,
如果我们确实喜欢 也会放在办公室专页上
or if we really like it, on our office bridge.
想了解更多并支持我们的工作
To learn more and to support our work,
请访问PATREON.COM/TEDED网站
please visit PATREON.COM/TEDED.
感谢收看
Thanks for watching.

发表评论

译制信息
视频概述

植物遇到动物昆虫的啃食也不会坐以待毙,那究竟如何抵御攻击呢?

听录译者

收集自网络

翻译译者

丁满

审核员

Y

视频来源

https://www.youtube.com/watch?v=Hja0SLs2kus

相关推荐