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Using points from the lecture, explain how the passion plant and the potato plant defend themselves from insects.
請用課上的觀點解釋說明龍珠果和馬鈴薯是如何抵抗昆蟲侵害的。
Listen to part of a lecture in a biology class.
請聽生物課上的部分內(nèi)容。
We all know that insects like to eat plants.
我們都知道昆蟲喜歡吃植物。
But some plants are able to develop ways to protect themselves from insects.
但是有些植物進(jìn)化出了抵抗昆蟲侵害的方法。
Today I'm gonna talk about some ways plants defend themselves.
今天我要講一講植物保護(hù)自己的一些方法。
Now, some plants have physical features that prevent insects from landing on them.
有些植物具有的體貌特征能夠防止昆蟲降落在它們身上。
Like the passion plant, for example, its leaves have little spiky hairs all over them.
就像龍珠果一樣，它的葉子上長滿了尖刻的毛。
They're like spikes, sticking out of the plant that are so numerous and dense
這些毛就像釘子一樣突出在植物表面，數(shù)量繁多且生長茂，
that they prevent insects from landing on the leaves.
它們能夠阻止昆蟲飛落在葉子上。
Basically there're just no room for the insects to land.
基本上根本沒有地方可以讓昆蟲降落。
And since insects can't land on the leaves they can't eat them.
既然昆蟲無法落在葉子上，它自然無法吃了它們。
So the little hairs serve as a physical feature that help protect passion plant from insects.
所以，這些毫毛就是保護(hù)龍珠果不受昆蟲侵害的體貌特征。
All right! But other plants protect themselves using chemical defenses, like the potato plant.
好了！不過另一些植物會用化學(xué)手段來保護(hù)自己，比如馬鈴薯。
The potato plant is able to release a chemical throughout its leaf system whenever an insect attacks it, starts eating the leaf.
無論什么時候昆蟲對它進(jìn)行攻擊，開始吃它的葉子，馬鈴薯都能通過葉系統(tǒng)釋放出一種化學(xué)物質(zhì)。
So, say an insect starts eating a potato plant's leaf,
假設(shè)一只昆蟲開始吃馬鈴薯的葉子，
that will cause the plant to react by releasing a chemical throughout its leaf system.
這會使植物以通過葉系統(tǒng)釋放化學(xué)物質(zhì)的方式來做出反應(yīng)。
The insect swallows this chemical as it eats.
昆蟲在食用葉子的過程中也吞下了這種化學(xué)物質(zhì)。
And this chemical discourages the insect from wanting to eat more of the plant.
而這種化學(xué)物質(zhì)會讓昆蟲不想再吃這種植物了。
How? Well, the substance makes the insect feel full, like it's already had enough to eat.
為什么？因為這種物質(zhì)會讓昆蟲有飽腹感，就像它已經(jīng)吃得夠多了一樣。
The insect no longer feels hungry so it stops eating the plant.
昆蟲覺得不餓了就會停止進(jìn)食。
So, by emitting this chemical, the potato plant protects itself from insects.
所以，通過釋放化學(xué)物質(zhì)，馬鈴薯能夠從昆蟲的侵害中保護(hù)自己。
