Good Taste Operation Ouch!

Are you ready for our Ouch! Snips?

Snip!

Ouch!

Exactly!

Well, it may look pretty hairy,

but it's actually from your tongue!

Take a look at this.

This is an MRI

scan of my tongue as I'm speaking,

and you can see it's pretty huge.

But speaking isn't the only thing

you need your tongue for.

One of the best things it does

is help you taste.

Your tongue is covered in small

hairlike projections,

as I'm going to show you. Right,

Xand, open your mouth nice and wide.

Eurgh! Not hair like that!

I said hairlike projections!

You can't see them

with your naked eye.

Take another look at this super

close-up of your tongue.

This red blob is called the papilla.

Your taste buds sit on the side

of it, and they contain tiny

hairlike projections called

microvilli to help you taste.

And if you look at your tongue, the

bumps you can see are the papillae.

And the more papillae you

have on your tongue,

the more taste buds you have and the

more sensitive to taste you are.

And you have more of them than we

do.

Because we're doctors!

No, Xand!

Because we're adults!

We have around 5,000 covering

our tongues, but you have 10,000.

That's twice as many.

And to prove it, Chris,

I've brought in a sample.

This sample is nine years old.

This isn't a sample. It's a child!

Anyway, the point is, we're going to

compare Chris' papillae with

the sample's, but first I need to

cover your tongues in blue food dye.

The blue dye will show up all the

papillae.

And now, the sample.

I have a name, you know, and it's

Hermione.

A very noisy sample!

Give me your tongue!

Nice blue tongue, Hermione!

Xand is putting a glass

slide on both our tongues to make it

easier to count the papillae.

Chris' papillae are those little

pale dots right there.

And these are Hermione's.

You can see that there's way

more on her tongue,

and that means more taste buds.

Good job, Hermione!

As we get older,

your taste buds deteriorate

and they aren't replaced, which is

why you will be much more

sensitive to strong flavours

like garlic than your mum or dad.

There are certain things,

though, like a cold,

that can play havoc with

everybody's sense of taste.

But why would having a bunged-up

nose affect your taste?

Well, we're going to show you.

Xand, meet Mr Bigmouth.

Hello! Argh!

You've cut him in half!

Now, when you eat food,

odour molecules are released

and swirl around your mouth,

but also right up into this.

This is the passage that

connects your mouth to your nose.

And right up here,

at the back of your nose,

are lots of sensors called olfactory

receptors, which sense and identify

different odour or smell molecules

and tell your brain what it is

you're tasting.

So, to show you this, we're going to

use an equally oversized bit of kit.

The smell molecule blower thingy.

Also, we'll need our

safety equipment

and these polystyrene balls

to represent

those smell or odour molecules.

Three, two, one... Blow!

The smell molecules in food are

released naturally as you chew.

Wow! That worked really well!

You can see how the smell

molecules race through

the back of the mouth and up

the tube connecting it to the nose

and right onto the olfactory

receptors, which instantly

recognise the smell and tell

your brain what you're tasting.

And your olfactory receptors can

also protect you

because they can tell if something

is bad before you eat it.

As soon as they whiff

something like off milk,

they alert your brain

so you know not to eat it.

But, Xand, what would happen

if Mr Bigmouth got a cold?

That would be disgusting!

We're going to need a lot of snot!

We're smearing our snot inside

the passages of our giant mouth

and nose,

just like when you have a cold.

Let's see what happens now that

Mr Bigmouth has got a big cold.

You ready?

BOTH:

Go!

Look. This time, the odour molecules

are getting stuck in the snot.

They aren't getting anywhere

near the olfactory receptors,

and that means no taste.

Yeah, Mr Bignose wouldn't be able to

taste anything at all.

Except for that one tiny

polystyrene ball.

So we've shown you that,

like Hermione's tongue,

you've got twice the number

of taste buds as us,

or your mum and dad, or any adult.

But as good as your tongue is,

you also need your nose

if you really want to savour

a flavour.

See you next time! Bye!

Bye!

Bye.

Bye.

Bye!

Bye.

Bye!