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鼓藻:充满“水晶”的对称藻类 – 译学馆
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鼓藻:充满“水晶”的对称藻类

Desmids: The Symmetrical Algae That's Full of Crystals

journey to the microcosmos
《微观旅途》
Cells divide,
细胞会分裂
and in the process, they create duplicates of single-celled organisms
在分裂过程中 生成单细胞的“复制品”
or they fill out the bodies of multicellular life.
或是填满多细胞生物的身体
It’s a process without which life as we know it could not exist
众所周知 没有细胞分裂 就没有生命存在
it sustains individuals and species alike.
它维持每个生命体及各个物种的存在
And on Journey to the Microcosmos
在通往微观世界的旅途中
we’ve been privy to this vital sequence quite a lot.
我们已经对细胞分裂的过程了解很多
At times, the division looks a bit like this
有时 细胞分裂看起来是这样的:
two cells in the middle of pulling apart from each other.
两个细胞从中间彼此分离
Or maybe they look a bit like these spiky guys,
或者像这些长着尖刺的家伙一样
clearly ready to move on to the next
显然它们已为和彼此分离后的
stage of their lives apart from each other.
下一阶段的生命旅程做好了准备
Except…these are not examples of cell division.
除了……这些并不是细胞分裂的例子
What you’ve been watching are not two single-celled organisms
你看到的 并不是处于细胞分裂末期
undergoing the last steps of what will finally separate them.
彼此分离的两个单细胞
No, this is one cell, belonging to the order of desmids,
不 这是一个单细胞 归类为鼓藻
a type of green algae that takes symmetry and beauty
鼓藻是一种绿藻类 它有美丽的对称形状
to a new and sometimes mysterious level.
又兼具新奇 神秘的特点
There are thousands and thousands of species of desmids,
鼓藻的种类成千上万
and the ways they exhibit their symmetry varies accordingly.
相应地 它们的对称形状也不尽相同
Sometimes they repeat a more rounded shape.
有时 它们的形状更偏向圆形
Other times, the microscopic mirror creates more of a crescent or rod shape.
其他鼓藻种类中 大多呈新月形或棒状
The underlying composition, however, follows a blueprint.
然而 鼓藻的组成都遵照同一个模型
These freshwater microbes are unicellular,
这些淡水微生物都是单细胞生物
though some species form long-chained colonies.
尽管有的鼓藻还能形成长链
Each desmid cell is made of two symmetrical halves, or semicells,
每个鼓藻细胞都由两个对称的半细胞组成
connected by a thin region called the isthmus
这两个对称半细胞由“缢缝”连接
that also holds the cell’s nucleus.
细胞核也在缢缝这片小区域
That word, isthmus, of course, is from geography
“isthmus”源自地理中“地峡”一词
a narrow strip of land that connects two larger pieces of land.
意为一条连接两块大陆的狭长地带
Inside this Micrasteria are,
在这个微星鼓藻内部
as you might tell from the green color, chloroplasts.
你能根据绿色得知叶绿体的存在
But there are only two of them
但其中只有两个叶绿体
each one large and knit into the various nooks and
每个叶绿体都很大 分布在每个半细胞中
crannies of their respective semicells.
塞满各个半细胞的所有缝隙和角落
It’s remarkable to consider just how green
仅仅一两个叶绿体也有明显的绿色
one or two chloroplasts can be.
这个现象异乎寻常
Just take a look at this dead Micrasterias for contrast,
将其与死去的细胞作对比
the vivid color gone with the rest of its life-giving processes.
鲜艳的颜色也会随着生命的陨落一起消失
Less elegant in theory, but
理论上来说 没有那么讲究 但是
as with everything they seem to do—striking to observe,
人们惊奇地发现 鼓藻的所有生命活动
many desmids release a gelatinous
比如它们会从细胞壁上的孔道
substance from their pores.
释放出一种胶状物质
This secretion forms a mucilaginous cell layer
这些分泌物形成粘液细胞层
around themselves,
分布在细胞周围
which acts as a boundary that might help keep the cell protected
以此与外界建立一个界限 以保护细胞
or might function to trap nutrients.
或用来储存营养物质
Even now, we’re not sure.
直到现在 我们仍不确定
We started off today comparing desmids to dividing cells,
今天 我们先将鼓藻和正分裂的细胞做比较
and maybe even trying to trick you into confusing the two.
甚至可能让你混淆这两个概念
But desmids do also divide.
但是鼓藻确实会分裂
Well, sometimes they actually reproduce sexually through conjugation.
事实上 有性世代的鼓藻通常行接合生殖
But in observing its asexual reproduction and cell division,
但通过观察它的无性生殖及细胞分裂
we can find an important though invisible difference
在鼓藻和其他类似的半细胞之间
between desmids and the otherwise similar semicells:
我们可以发现一个十分重要 但难以察觉的区别
their age.
它们的“年龄”
Desmids divide at the isthmus,
鼓藻细胞在缢缝处(接触点)分裂
separating the two half cells
分裂成两个半细胞
that then have to grow out a new semicell.
接着 两个半细胞上分别长出一个新的半细胞
This means that within each desmid,
这意味着每一个鼓藻细胞中
each half cell might be different ages.
每个半细胞都是不同的“年龄”
You might very well be looking at whatever
你可以将观察到的绿色鼓藻中
the green algae semicell equivalent of an adult is,
其中一个半细胞视为成年人
conjoined through the isthmus to its younger mirror.
通过缢缝与更年轻的另一个半细胞结合
It’s like having half of your body be a child.
这就像是 你身体的一半仍然稚嫩
Desmids aren’t unique in having some kind of symmetry
鼓藻并不是唯一具有对称性的生物
we see symmetry all across nature,
在大自然中 对称性随处可见
To the extent where asymmetry might reveal more about
在某种程度上 和对称性相比
how an organism works than symmetry does.
不对称性更能揭示有机体的生活方式
But this kind of mirrored, semicell arrangement
但是这种对称排列的结构
is particularly striking to look at and to consider.
更值得特别关注和思考
which leads, naturally, to the question…why?
也自然而然的引出这个问题:为什么(是对称的)呢
We haven’t yet dug up any scientific literature
我们并没有任何科学文献
that can explain what advantage this symmetry might provide,
来解释对称性可能提供的优势
though of course, we might also be seeking
当然 在现实情况尤为复杂时
the simplicity of easy evolutionary answers when reality is more complex.
我们也尝试用简单的 “生物进化“来解释(这一现象)
But if you do have an answer or even just a guess,
但如果你已经有了答案 或只是猜测
let us know. Because at the moment,
都可以告诉我们 因为当前
we don’t have any.
我们没有任何答案
Symmetry, however, is only one part of
然而 对称性只是鼓藻细胞
what makes desmids so striking to look at.
引人注目的一部分
Most desmids have these strange crystals inside of them.
很多鼓藻细胞里都有这些奇怪的晶状体
The crystals are tiny
晶状体都很小
and their paths are impacted by the movement of individual water molecules
且其运动路径受到细胞内水分子的运动
that fill up the cell and collide into those crystals,
以及彼此之间碰撞的影响
creating frantic movements.
这造成晶状体的剧烈运动
That is also known as Brownian motion.
也称为布朗运动
As we shine polarized light on those crystals,
当我们用偏振光照射这些晶状体
we can see them dancing and lighting up the green around them
我们可以看到它们在绿光下翩翩起舞
as if it’s a holiday season in the microcosmos.
就像是微观世界里的节日
But, what are the crystals for?
但晶状体有什么作用呢
They have to be for something.
它们肯定有特定的功能
But again, we do not know.
但我们确实也不知道
Microbiologists are still working to figure it out.
微生物学家仍然在努力找出答案
But whatever specific need they are filling,
但不管晶状体具有什么特定功能
these crystals may play a role
或许这些晶状体能参与解决
in parsing through a big chemical question:
一个化学难题:
how do we clean up radioactive waste?
我们怎么清理放射性废物呢
Now, this might not be a question you’d expect to be answered in the form of Closterium,
你可能没想到 长得像根绿色香蕉的新月藻
a desmid that looks a bit like a green banana.
还有这么一个功能吧
But Closterium collects barium from its surroundings.
但新月藻会从四周收集吸收钡元素
As the barium gets shuffled into the Closterium’s sulphate-rich vacuoles,
当钡被富含硫酸盐的液泡吸收
it precipitates into crystals,
就会析出晶体
which you can see compartmentalized but still moving in the tip.
这些被析出的晶体仍在尖端移动
Again, these crystals are mysterious
再次声明 这些晶体很神秘
we don’t know what purpose they serve,
我们并不了解这些晶体的功能
or even if they even serve a purpose.
或者它们是否具有功能
But in studying them, scientists have observed that under certain conditions,
但在研究过程中 科学家观察到 在某些情况下
Closterium moniliferum can collect strontium from the water
圆月藻能从水中吸收锶元素
and within 30 to 60 minutes,
在30至60分钟内
precipitate it in the very same vacuoles that it uses to create its barium crystals.
在析出钡晶体的同一液泡里 析出锶晶体
This talent might be a handy one to have
在发生核灾难后
when say you’re tasked with selectively clearing out
选择性地清除含放射性锶的水源时
radioactive strontium-containing water following a nuclear disaster.
新月藻的这一功能就十分有效
However, we wanted to note that the experiments demonstrating that
然而我们也想让你知道
Closterium can take in strontium
新月藻能吸收锶的实验
were not designed to test to see how well the organism can handle radioactivity,
并不是用来测试该生物体处理放射性的能力
so while it can definitely pick up strontium,
尽管它确实可以吸收锶
it might not be happy picking up radioactive strontium.
但它可能并不会“很乐意”
So, the application here, still a hypothetical.
所以这一应用仍只是个假想
Scientific caveats aside, it’s tempting to fully indulge that train of thought, and
撇开科学警告不谈 完全沉溺于这一假想的确很诱人
and to envision a world where microbes save us from ourselves.
想象一下 微生物来拯救我们的世界
After all, these are organisms
毕竟 这些生物体
whose own symmetric morphology imply order,
各自都具备一定的形态
even as they house the random motion of mysterious, jittery crystals.
其中还包含随机运动的神秘晶状体
But whether desmids serve to help us contend with future disasters or not,
不管鼓藻是否能帮助人类与未来的灾难做斗争
their striking shapes and structure provide us with another service,
它们奇异的形状和结构为我们提供了另一样东西
the simple beauty of the microcosmos.
微生物的简约之美
Thank you for coming on this journey with us
感谢您和我们一起
as we explore the unseen world that surrounds us.
踏上探索周围未知世界的旅程
And thank you especially to all of these people who make Journey to the Microcosmos possible
特别感谢所有从众筹网站赞助本栏目
by supporting us on Patreon.
让《微观旅途》成功创办的人们
If you want to see more from our Master of Microscopes, James Weiss,
如果想要观看更多《显微镜大师:詹姆斯·维斯》
check out Jam and Germs on Instagram.
您可以在Ins上搜索Jam And Germs
And if you want to see more from us here at Journey to the Microcosmos,
如果想收看《微观旅途》栏目的更多作品
there’s always a subscribe button somewhere nearby.
那么就点击订阅吧

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视频概述

解开鼓藻的奥秘~

听录译者

收集自网络

翻译译者

刘小贵

审核员

审核员 V

视频来源

https://www.youtube.com/watch?v=qV0udTvYK6M

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