You're Amazing

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You are amazing. You literally glow.

No seriously, humans glow in the dark.

Just barely. We only emit a very

small amount of light. Such a

tiny amount that only specialized

equipment can actually see it.

The brightness of the light is

about a thousand times dimmer

than what humans can perceive.

This glow is known as biophoton

emission, which is slightly different

from bioluminescence. The reason

we produce the light is something

related to our metabolism and

highly reactive free radicals

interacting with free-floating

lipids and proteins and a whole

lot of other stuff that I'm not

about to try and explain.

Also...you're tough...kinda.

Your skeleton is made of bones

(who knew) and those bones are

stronger than steel! Well...kind of...

Bones are stronger than steel

by weight, so a regular bone isn't

going to be stronger than a steel

bone since the steel is way more

dense and thus weighs a lot more

and is thus much stronger. But

if you made a steel bone using

a small enough amount of steel

that it weighed the same as a

regular bone, the regular bone

would be stronger than the steel bone.

Your femur (also known as the

thighbone) is more special than

most of your bones. It's not only

the largest bone in your body

but also the thickest and strongest.

It holds a lot of weight and often

has a lot of force applied to

it (such as when you're walking

or running) so it had to be created

incredibly strong. But it's probably

far stronger than you'd expect.

The femur is so strong that it

can support about 30 times your

body weight! That means just one

femur from an average person weighing

62 kilograms could support nearly

2 tonnes, about the weight of

an average car! And if you weighed

more, such as 100 kilograms, 4

of your femurs would be able to

support an entire semi-truck!

Well, an empty one at least and

also ignoring the fact that most

humans don't have four legs. But

that's still absolutely amazing!

Oh, and another special bone

is the hyoid bone. The hyoid bone

is the only bone in the human

body which is not directly connected

to another bone. It's important

for really minor things like um...

speaking and swallowing.

Anyway, something else, besides

your bones, that makes you tough

is your heart. It doesn't really

matter how soft-hearted you are,

you have an incredibly tough

or rather resilient heart. Your

heart, despite all its intricate

and seemingly fragile mechanisms,

has been working non-stop for

your entire life. No rests, no

stops for repair, just continuously

pumping blood and keeping you alive.

At least for most of us.

Your heart pumps blood through

your blood vessels at up to 40

centimeters per second, the blood

completing 1 entire circuit of

your body in about 20 seconds!

In those 20 seconds it pumps around

5 liters of blood a total of 4

kilometers. That means in the

average lifetime of 70 years the

heart pumps around 600 million

liters of blood, which is about

this much. The total distance

the blood was pumped would be

around 500 million kilometers,

about the distance around the

Earth 12 thousand times or 3 times

the distance from Earth to the Sun.

500 million kilometers, 600 million

liters of blood, 2.5 billion beats,

and absolutely no breaks for rest.

I'm getting tired just thinking

about it.

But you want to know something

else that never stops? Your ears.

You are constantly hearing the

sounds around you. Even while

you're sleeping or even while

you're unconscious, you are constantly

hearing sounds. It's just that

sometimes your brain chooses to

ignore the sound or fails to process

the sound. For example, you may

have been woken up before because

of a loud noise. In order for

you to hear that noise, you had

to be listening.

Which, speaking of sleeping,

your brain is very active with

all your neurons firing billions

or trillions of times per second.

But what's crazy about this is

that your brain can sometimes

become more active while you're

sleeping, exceeding the activity

levels of the brain when you're awake.

And there's something else fascinating

about your brain. Well, there

are a lot of fascinating things

about your brain, but just one

of those things is that your brain

uses only about 20 watts of electricity.

That is incredibly power efficient!

For comparison, even a very basic

laptop will generally use around

20 watts while doing basic work

and more powerful laptops can

easily use over 100 watts when working!

But your brain uses only 20 watts

to process super high-resolution

video and audio and perform billions

of mathematical calculations,

plus much, much more. It's just

amazing that the brain does so

much with so little energy.

But, as you can probably guess,

this isn't the only amazing thing

about you. Not just because I've

said other things already but

also because you have around 68

trillion cells in your body, although

that's a very rough estimate.

About 38 trillion of those are

bacteria, which does in a way

mean that you are more bacteria

than you are human. Of those remaining

30 trillion cells, which are human

cells instead of bacteria, about

84% of them are red blood cells.

Real surprising, I know. But anyway,

red blood cells (and actually

several other types of cells)

don't have DNA once mature, but

taking all the cells which do

have DNA, each cell contains around

2 meters of DNA. So taking that

2 meters of DNA and multiplying

it by the remaining 3 trillion

human cells with DNA, we get a

total measurement of about 6.7

billion kilometers of DNA. About

enough to wrap around the entire

Earth 166 thousand times, or about

the distance to the Sun 45 times!

If we add in all the DNA from

the bacteria in your body, the

total length of DNA would be about

52 million kilometers longer.

Sooo...if we combined the DNA

from every person on the entire

planet, the DNA would stretch

all the way around our entire

galaxy 21 times! All that compressed

onto a tiny little ball floating

in the middle of space...

And that's just the DNA of humans!

If we added the DNA of all the

other living organisms into that,

the length would be far, far longer!

I'm not going to calculate it

because...um...there's this thing

called...uh...thyme and um...these

things called leaves...and uh...

basically time leaves-

Anyway, while I'm not going

to calculate it, other people

have estimated that the total

length of DNA on Earth is about

8 trillion light-years long. Which

is enough to wrap around the entire

observable universe 27 times!

Now that is what I like to call...

the- the end-screen. That- That's

the end-screen which basically

means the video's over and I'm

trying to get you to watch more

of my videos because my videos

are packed with really cool facts

and are actually pretty bor-