Human sperm vs. the sperm whale - Aatish Bhatia

Translator: Dhini Wahyu Utami Reviewer: Reno Kanti Riananda

In 1977, the physicist Edward Purcell

Di tahun 1977, fisikawan Edward Purcell

calculated that if you push a bacteria and then let go,

memperhitungkan jika Anda mendorong bakteri dan melepasnya,

it will stop in about a millionth of a second.

ia akan berhenti dalam sekitar seperjuta detik.

In that time, it will have traveled less than the width of a single atom.

Dalam waktu itu, ia akan berpindah jarak kurang dari lebar sebuah atom.

The same holds true for a sperm and many other microbes.

Hal yang sama berlaku untuk sel sperma dan banyak mikroba lainnya.

It all has to do with being really small.

Semua itu ada hubungannya dengan ukuran mereka yang sangat kecil.

Microscopic creatures inhabit a world alien to us,

Makhluk mikroskopis tinggal di dunia yang asing bagi kita,

where making it through an inch of water is an incredible endeavor.

di mana menyelami satu inci air saja adalah pencapaian yang luar biasa.

But why does size matter so much for a swimmer?

Namun, mengapa ukuran sangat penting bagi perenang?

What makes the world of a sperm so fundamentally different

Apa yang membuat dunia sebuah sel sperma sangat jauh berbeda dengan paus sperma?

from that of a sperm whale?

To find out, we need to dive into the physics of fluids.

Untuk mengetahuinya, kita harus menyelami dunia fisika fluida.

Here's a way to think about it.

Begini caranya.

Imagine you are swimming in a pool.

Bayangkan Anda berenang di kolam.

It's you and a whole bunch of water molecules.

Di sana ada Anda dan sekumpulan molekul air.

Water molecules outnumber you a thousand trillion trillion to one.

Anda kalah jumlah dengan molekul air, seribu triliun triliun banding satu.

So, pushing past them with your gigantic body is easy,

Jadi, mudah saja bagi tubuh raksasa Anda untuk melaju melewati mereka.

but if you were really small,

tetapi jika Anda berukuran sangat kecil,

say you were about the size of a water molecule,

misalnya, sebesar molekul air,

all of a sudden, it's like you're swimming

tiba-tiba terasa seperti sedang berenang

in a pool of people.

dalam kolam yang ramai.

Rather than simply swishing by all the teeny, tiny molecules,

Anda tidak lagi melewati molekul yang sangat kecil,

now every single water molecule

sekarang tiap-tiap molekul air

is like another person you have to push past

terasa seperti orang yang harus Anda lewati

to get anywhere.

untuk berpindah tempat.

In 1883, the physicist Osborne Reynolds

Tahun 1883, fisikawan Osborne Reynolds

figured out that there is one simple number

menemukan bahwa ada satu angka sederhana

that can predict how a fluid will behave.

yang dapat memprediksi perilaku fluida.

Dinamakan angka Reynolds,

It's called the Reynolds number,

and it depends on simple properties like the size of the swimmer,

dan angka tersebut bergantung pada ciri sederhana seperti ukuran perenang,

its speed, the density of the fluid,

kecepatan, densitas,

and the stickiness, or the viscosity, of the fluid.

dan viskositas cairan.

What this means is that creatures of very different sizes

Maksudnya, makhluk dengan berbagai ukuran

inhabit vastly different worlds.

hidup di dunia yang sangat berbeda.

For example, because of its huge size,

Contohnya, karena ukurannya yang besar,

a sperm whale inhabits the large Reynolds number world.

paus sperma hidup di dunia dengan angka Reynolds yang besar.

If it flaps its tail once,

Jika ekornya mengepak sekali,

it can coast ahead for an incredible distance.

paus dapat berpindah tempat jauh sekali.

Meanwhile, sperm live in a low Reynolds number world.

Sementara sperma hidup di dunia dengan angka Reynolds rendah.

If a sperm were to stop flapping its tail,

Jika sperma berhenti mengepakkan ekornya,

it wouldn't even coast past a single atom.

satu atom pun tidak akan ia lewati.

To imagine what it would feel like to be a sperm,

Untuk membayangkan rasanya menjadi sperma,

you need to bring yourself down to its Reynolds number.

Anda harus menyamakan angka Reynolds Anda dengan mereka.

Picture yourself in a tub of molasses with your arms moving

Bayangkan Anda di bak penuh molase, tangan Anda bergerak

about as slow as the minute hand of a clock,

lambat selambat jarum menit jam,

and you'd have a pretty good idea of what a sperm is up against.

Anda akan sedikit tahu apa yang dirasakan oleh sperma.

So, how do microbes manage to get anywhere?

Jadi, bagaimana mikroba bisa berpindah tempat?

Well, many don't bother swimming at all.

Kebanyakan tidak berenang sama sekali.

They just let the food drift to them.

Membiarkan makanan mendatangi mereka.

This is somewhat like a lazy cow

Seperti sapi pemalas

that waits for the grass under its mouth to grow back.

yang menunggu rumput di bawah mulutnya tumbuh kembali.

But many microbes do swim,

Namun, banyak juga mikroba yang berenang,

and this is where those incredible adaptations come in.

dan di sinilah adaptasi luar biasa itu dimulai.

Satu trik yang mereka lakukan adalah mengubah bentuk ekor mereka.

One trick they can use is to deform the shape of their paddle.

By cleverly flexing their paddle

Dengan melenturkan ekor

to create more drag on the power stroke than on the recovery stroke,

untuk menciptakan tarikan lebih pada langkah daya,

single-celled organisms like paramecia

single-celled organisms like paramecia

manage to inch their way through the crowd of water molecules.

dapat berenang melewati sekumpulan molekul air.

But there's an even more ingenious solution

Namun, ada cara yang lebih baik

arrived at by bacteria and sperm.

bagi bakteri dan sel sperma.

Instead of wagging their paddles back and forth,

Alih-alih mengepakkan ekornya terus-menerus,

they wind them like a cork screw.

mereka memutarnya seperti kotrek.

Just as a cork screw on a wine bottle

Seperti kotrek pada botol anggur

converts winding motion into forward motion,

yang mengubah gerak ulir menjadi gerak maju,

these tiny creatures spin their helical tails

makhluk mungil ini memutar ekor heliks mereka

to push themselves forward

untuk bergerak maju

in a world where water feels as thick as cork.

di dunia di mana air terasa setebal sumbat botol.

Other strategies are even stranger.

Cara lainnya lebih aneh.

Some bacteria take Batman's approach.

Beberapa bakteri memakai cara Batman.

They use grappling hooks to pull themselves along.

Mereka mamakai kait untuk menarik diri mereka sendiri.

They can even use this grappling hook

Mereka bahkan dapat memakai kait ini

like a sling shot and fling themselves forward.

seperti ketapel dan meluncur maju.

Others use chemical engineering.

Lainnya menggunakan cara kimia.

H. pylori lives only in the slimy, acidic mucus

H. pylori hidup hanya di mukus berlendir dan asam

inside our stomachs.

di dalam perut kita.

It releases a chemical that thins out the surrounding mucus,

Ia mengeluarkan zat yang mengikis mukus di sekelilingnya,

allowing it to glide through slime.

agar ia bisa bergerak.

Maybe it's no surprise

Tidak mengagetkan

that these guys are also responsible for stomach ulcers.

jika mereka juga bertanggung jawab atas sakit lambung.

So, when you look really closely at our bodies and the world around us,

Jadi, saat Anda melihat tubuh dan dunia sekitar lebih dekat,

you can see all sorts of tiny creatures

Anda bisa melihat semua makhluk mungil

finding clever ways to get around in a sticky situation.

mencari cara cerdas untuk lolos dari situasi sulit.

Without these adaptations, bacteria would never find their hosts,

Tanpa adaptasi semacam ini, bakteri tidak akan menemukan inangnya,

and sperms would never make it to their eggs,

dan sel sperma tidak akan bisa sampai ke telurnya,

which means you would never get stomach ulcers,

yang artinya perut Anda tidak akan pernah sakit,

but you would also never be born in the first place.

tapi Anda juga tidak akan lahir.

(Pop)

(Tuing)