Care to take a tour
inside your own body?
No, I don't suggest you do capsule endoscopy,
you know, the one that takes pictures
inside your digestive tract?
Or an X-ray.
Let's take the most sophisticated,
hypothetical tour,
where you would be your own guide.
What I have in mind might seem
a bit out-there, but picture this.
What if all of your organs were mini yous,
running their own departments,
and dealing with each other's characters?
Your body is a complex machine
made up of nearly 100 trillion cells.
They're constantly replicating, dying,
and being replaced with new ones.
You have five vital organs
that you can't live without,
and a few organs that you don't really need.
And now you get a chance to meet them all.
This is the head of the circulatory department,
and the hardest-working of all of your organs.
Your heart is a muscular organ
that pumps blood throughout your body
all day and all night.
It delivers oxygen- and nutrient-rich blood
to all parts of your body via arteries,
and receives oxygen- and nutrient-poor blood
back via veins.
Your heart slows down when you sleep.
But when it gets signals of danger,
it starts pumping blood faster,
to deliver more oxygen to your cells and tissues.
But it doesn't work alone.
It receives deliveries of oxygen from your lungs,
the head of the respiratory department.
"Oxygen in, carbon dioxide out.
Move it out!
I don't need any of this waste in the system."
Do you hear this?
That is your digestive system, two floors down,
and it's breaking down your lunch.
But before we get there,
you've got to meet someone upstairs.
Your mouth is like an intern
working for a few departments simultaneously.
It can cover for your nose and take in oxygen
for the respiratory department.
And it also begins the process of digestion
for the digestive department.
Then the food travels down through your esophagus,
all the way to the stomach.
Your stomach produces gastric juice
that breaks down proteins,
and kills off potentially dangerous bacteria.
What used to look like a yummy slice of pizza,
turns into this paste,
and is released into your small intestine.
This 6-meter-long (20 ft) organ
absorbs all the nutrients from your lunch,
and sends them through your bloodstream and into the liver.
Your liver, true neat freak.
It breaks down drugs, detoxifies all the harmful chemicals,
and sends them out of your body as waste.
And it hates when you get drunk.
And these are the kidneys.
Just like the liver, these guys
are a couple of little neat freaks.
They clean the waste and excess fluid from your blood,
and send all that stuff out of your body as urine.
All these processes are controlled
from the command center, your brain.
It has about 100 billion employees, the nerve cells.
And with their help, the brain sends and receives messages
from all the other departments of your body.
Yep, your brain's got some control issues.
Everything has to be as it says.
Then you've got some workers that aren't that essential.
Take the spleen.
Hiding at the back of the ribs,
and on the left side of the abdomen,
it essentially has the same function as the liver.
And here's another one, the appendix.
It sits at the junction of the large and small bowels,
waiting to catch an inflammation from the intestine.
That's when you get appendicitis,
and need to remove this sneaky organ from your body.
But most of the workers inside your body are essential.
They all come with their own set of responsibilities,
and if they fail, it's not good for the entire system.
The defense department, your immune system,
looks into all the cells that enter your system.
It's always ready to attack bacteria,
viruses, and parasites.
But sometimes that's not enough,
and your body needs external help
in the form of medication.
Jokes aside, if you could take a look
inside your body any time you wanted,
you'd be able to detect if anything is wrong with it,
and live longer.
And if increasing your life longevity
is something you're interested in,
we've got another show for you,
to help you survive whatever awaits you.