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蚊子是怎么用6根针来吸你血的 – 译学馆
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蚊子是怎么用6根针来吸你血的

How Mosquitoes Use Six Needles to Suck Your Blood | Deep Look

这是世界上最致命的动物
This is the deadliest animal in the world.
蚊子每年使成千上万的人死去……这些最脆弱的人:孩子
Mosquitoes kill hundreds of thousands of people each year… the most vulnerable people: children,
孕妇
pregnant women…
再没有其他动物的叮咬杀死更多人 或使更多人生病了
No other bite kills more humans… or makes more of us sick.
再没有其他动物的叮咬杀死更多人 或使更多人生病了
No other bite kills more humans… or makes more of us sick.
再没有其他动物的叮咬杀死更多人 或使更多人生病了
No other bite kills more humans… or makes more of us sick.
那么是什么让蚊子的叮咬如此有杀伤力呢?
So what makes a mosquito’s bite so effective?
首先 它们是有动机的
For starters, they’re motivated.
只有雌性蚊子才咬人 它们需要血液的养分才能产卵 还需要一滩水让卵
Only females bite us. They need blood to make eggs… And a pool of water for their babies
在其中孵化
to hatch in.
只要一个小水杯就足够了
Even a piece of trash can hold enough.
乍一看 过程很简单 这只蚊子正把她口器插入人的皮肤内
At first glance, it looks simple — this mosquito digging her proboscis into us.
但它所用的工具可不简单
But the tools she’s using here are sophisticated.
首先 保护鞘收缩 看到它弯曲了吗?
First, a protective sheath retracts – see it bending back?
如果你用显微镜观察一只蚊子的头部 你就可以看到护鞘内的器官
If you look at a mosquito’s head under a microscope, you can see what that sheath protects.
里面有六根针!
And inside *there* are six needles!
其中两根长有细锯齿 雌性蚊子用它们来锯开皮肤 它们太锋利了
Two of them have tiny teeth. She uses those to saw through the skin. They’re so sharp
你几乎感觉不到针的推进
you can barely feel her pushing.
另外两根针负责锯刺周围的组织 以便她吸血
These other two needles hold the tissues apart while she works.
从皮肤下面 你可以看到她在四处探测 寻找血管
From under the skin, you can see her probing, looking for a blood vessel.
位于另一根针上的感受器能接收由我们的血管自然散发出来的化学物质
Receptors on the tip of one of her other needles pick up on chemicals that our blood vessels
并以此来指导她找到血管
exude naturally and guide her to it.
然后 她把这根针当食管来用
Then she uses this same needle like a straw.
当她吸饱后 她会分离出血液中的水分 并将它排出 看到水滴了吗?
As her gut fills up, she separates water from the blood and squeezes it out. See that drop?
这样做是为了腾出空间来摄取更多有营养的红细胞
That frees up space to stuff herself with more nutritious red blood cells.
最后一根针会释放化学物质 防止我们的血液凝固
With another needle, she spits chemicals into us. They get our blood flowing more easily,
之后还会留下发痒的红肿
and give us itchy welts afterwards.
有时候 在她离开前 她还会在唾液里留下一份离别礼物:
And sometimes, before she pries herself away, she leaves a parting gift in her saliva:
致病甚至致死的病毒或寄生虫
a virus or a parasite that can sicken or kill us.
这对她本身并没有影响 这些病毒和寄生虫只是搭个便车而已
There’s nothing in it for her. The viruses and parasites are just hitching a ride. But
但这就是我们和蚊子不共戴天的原因
this is what makes mortal enemies out of us and mosquitoes.
蚊子吸我们的血 有时候我们让它们血肉模糊 但通常的情况是 我们不够快
They take our blood. Sometimes we take theirs. But often, not soon enough.
很好 你还在这儿
Good. You’re still there.
这些是尖音库蚊的幼虫 也是加利福尼亚当地常见的家蚊
. These are the larvae of Culex pipiens, a.k.a. the common house mosquito
很恶心 对吧? 把你的排水沟清干净就可以避免这种情况了
here in California. Gross, right? Well, you can avoid them by emptying your
宠物的水碗也要清干净 如果你还在收看的话 订阅我们的频道吧! 你将会看到更多
rain gutters. Pet water dishes too. While you’re at it, subscribe! We have so many more
有关科学的视频 下次节目再见!
science videos coming your way. See you next time!

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