Transcriber: Andrea McDonough Reviewer: Bedirhan Cinar
I'm going to take you on a journey
into some hidden worlds inside your own body
using the scanning electron microscope.
These microscopes use a beam of electrons
to illuminate things that are too small
to be seen by the photons of visible light.
And to put this in context,
if you mentally divide one tiny millimeter
into a thousand parts,
each one of those parts is a micrometer,
or micron for short.
If you then divide one micron
into another thousand parts,
each one of those is a nanometer.
And it's nanometers and microns
that are the domain
of the scanning electron microscope.
So, let's start with something on the body
that we can measure at about 100 microns wide,
and that would be a human hair,
which now you can see is covered with scales,
just like all of our hairs,
and in fact, just like all mammal hairs.
We're going to plunge into the body now,
and we've landed in the thyroid gland.
Here we're looking at proteins
that are being secreted into a storage chamber
where they are going to develop
into the mature thyroid hormones
before being released into the body.
And at this point you might be wondering
if these colors are real.
The answer is no.
Electron images only happen in black and white.
I often colorize my images for various reasons,
but I don't change the structures,
so the strucutres that you're seeing
are all exactly as they were
when I photographed them in the microscope.
We're going to take a detour
and zoom in on the heart muscle now.
And the heart muscle has this curious structure
that's kind of like corrugated cardboard.
That's what allows the heart to expand and contract as it's beating.
Let's go look at a lung with pneumonia.
Here we've got a white blood cell
poking around in an air sac,
looking for something to clean out
like a little vacuum cleaner.
This is your immune systems at work.
So what are the kinds of things
that we don't want to be breathing,
besides bacteria and viruses?
Well, we all know to stay away from asbestos
and now we can see why.
This is a close-up view of the mineral
that asbestos is made from,
and now you can see that it's composed of
many tiny, fine little needles.
Each one of those needles is a single crystal.
And in this picture, they're begininng to pry apart
and tangle up into a spiky mess,
not for breathing.
What else might we want to avoid breathing?
Well, how about diesel fuel?
We're looking here at the particles of diesel soot,
and these are extraordinarily tiny.
In fact, each one of these little particles
is only about 50 nanometers wide.
We'll go and look at some blood now.
We've got a collection
of nice, fat, happy, healthy red blood cells,
but they're all tangled up in a network of fibers.
This is how the body makes a blood clot.
And so, it surrounds a group of red blood cells
and other cells, and traps them
so the blood can't flow.
We've got two more blood cells here,
but they're not normal
like the ones in the blood clot image.
These are distorted.
You can see that they're curling up
and beginning to grow what's going to become spikes.
These are sickle cells
and these are what cause the condition
of sickle cell amenia.
We've gone into the mouth now
and we've landed on dental plague,
which you can see is covered with bacteria,
and in fact dental plague is host
to about 1,000 different species of bacteria.
Lovely to think about.
And now we are on to other teeth.
We're on the surfaces of the,
or the internal surfaces of the teeth themselves.
The smaller one is a baby tooth
that had just fallen out of the mouth
of a young friend of mine,
and I want to call your attention to the little holes.
Those little holes are the tops
of a whole network of tiny little tubes
that circulate nourishing fluids inside your teeth.
And we can see those tubes
a little better in the larger picture
because some of them are in cross-section.
But in fact, this larger picture is showing you
a portion of a tusk, which you may know
is simply a great big, elongated tooth,
so you would expect to see the same features
between your teeth and a tusk.
But that larger tusk picture is also rough
by comparison to the young baby tooth.
That's because it's many, many thousands of years old.
It's also partly fossilized.
And, between these two pictures,
now you can see how your teeth relate
to the tusk of an Ice Age mammoth.
We're shooting up north now into the brain,
and we can see these pink cells down at the bottom.
Those are the neurons of memory.
And I'm going to leave you with this picture
because I know you're going to take
a lot of happy memories away
from your exciting day at TED
and now you can visualize where those memories
are being stored in your own brain.
Thank you.