0:00:23 > 0:00:25He's Dr Chris.
0:00:25 > 0:00:29- He's Dr Xand. - And, yes, we're twins.
0:00:31 > 0:00:33Do you know how brilliant your body really is?
0:00:33 > 0:00:36My finger's got yellow pus in it.
0:00:36 > 0:00:39Well, we're going to show you. Yay!
0:00:39 > 0:00:42In this series we'll be pushing our bodies to their limits...
0:00:42 > 0:00:43I like the sound of this!
0:00:43 > 0:00:47..by doing extraordinary experiments on each other.
0:00:47 > 0:00:49This is my sick.
0:00:49 > 0:00:51To uncover what goes on inside.
0:00:51 > 0:00:53Ah!
0:00:53 > 0:00:54And out.
0:00:54 > 0:00:55Wow, that's amazing!
0:00:55 > 0:00:58From the bizarre...to the incredible.
0:00:58 > 0:01:00So now I'm seeing things.
0:01:00 > 0:01:02It's time to find out what you're made of.
0:01:02 > 0:01:06Chris? Chris? Chris?
0:01:07 > 0:01:08Coming up on...
0:01:08 > 0:01:09Operation Ouch!
0:01:13 > 0:01:15Courtney's ear needs flushing.
0:01:17 > 0:01:19Xand does some painting with his wee.
0:01:21 > 0:01:24And we meet some creepy crawlies that are a bit too
0:01:24 > 0:01:25close for comfort.
0:01:25 > 0:01:26Aww, it's moving!
0:01:30 > 0:01:33Medical teams always expect the unexpected.
0:01:33 > 0:01:36Let's see how they fix our first patient.
0:01:39 > 0:01:41'In Accident and Emergency,
0:01:41 > 0:01:43'nine-year-old Courtney has come in with
0:01:43 > 0:01:45'her mum, her dad and something else.'
0:01:45 > 0:01:49I've got a bit of a pencil stuck in my ear.
0:01:49 > 0:01:51'You what?
0:01:51 > 0:01:52'Did I ear that right?'
0:01:52 > 0:01:56I was messing around with it and I put it in my ear.
0:01:56 > 0:01:59'OK. I did. So what colour is it?'
0:01:59 > 0:02:01It's a yellow pencil.
0:02:01 > 0:02:06- 'Never mind the colour, Xand. - Well, how did it get there?'
0:02:06 > 0:02:10Courtney was in her bedroom with her colouring pens and pencils.
0:02:10 > 0:02:13One in particular caught her eye. It was the yellow one.
0:02:13 > 0:02:15Ooh, is that her favourite colour, Chris?
0:02:15 > 0:02:18The green one looks nice, or the blue one.
0:02:18 > 0:02:21No, Xand, something about the yellow one appealed to her.
0:02:21 > 0:02:23Anyway, she stared at it.
0:02:23 > 0:02:25It stared back, wondering if it would be chosen.
0:02:25 > 0:02:28"Colour in with me," it thought. I'll be your sun.
0:02:28 > 0:02:32I'll be your sand. I'll be your rubber ducky.
0:02:32 > 0:02:34Why would she want to draw a rubber ducky?
0:02:34 > 0:02:36I couldn't think of anything else yellow.
0:02:36 > 0:02:37- Just go with it.- OK.
0:02:37 > 0:02:40- "That might fit in my ear," Courtney thought.- Oh, dear.
0:02:40 > 0:02:43- I see where this is going. - So did she.
0:02:43 > 0:02:45Ouch!
0:02:45 > 0:02:48'That crayon must be hiding. can you see it, dad?'
0:02:50 > 0:02:54'Here's Dr Julian Warren to investigate.'
0:02:54 > 0:02:55What colour's the crayon?
0:02:55 > 0:02:56'Not you as well, doc.'
0:02:56 > 0:02:58- Yellow.- Is that your favourite colour?
0:02:58 > 0:03:00- No.- No. OK.
0:03:00 > 0:03:03- 'Tell us what is your favourite colour, Courtney?'- Red.
0:03:03 > 0:03:05'Red. Right. Glad we got that sorted.'
0:03:05 > 0:03:09Shall we have a little look and see if we can get it out?
0:03:09 > 0:03:11'First, Dr Warren needs to check exactly
0:03:11 > 0:03:13'where the missing crayon's hiding.'
0:03:13 > 0:03:16Yeah. We can see that quite clearly.
0:03:16 > 0:03:20'Thank goodness he's found it. So where exactly is it?'
0:03:21 > 0:03:25Your ears are divided into three parts, the inner, middle
0:03:25 > 0:03:28and outer ear, connected by the ear canal.
0:03:28 > 0:03:31The ear canal is roughly 2.5 centimetres long
0:03:31 > 0:03:34and that's where Courtney's yellow crayon is stuck.
0:03:34 > 0:03:36If it's left in there it could cause damage or infection.
0:03:36 > 0:03:39Let's see if we can get that out, shall we?
0:03:39 > 0:03:40'What's the plan then, doc?'
0:03:40 > 0:03:43We'll take her through to the procedure room and we'll try
0:03:43 > 0:03:45and see if we can get a little metal probe behind it
0:03:45 > 0:03:48and hook it out, but hopefully we'll get it out today.
0:03:48 > 0:03:52'In the treatment room, Doctor Warren goes crayon fishing
0:03:52 > 0:03:56'with his special hook, but will he catch anything?'
0:03:56 > 0:03:59It's a case of trying to see if we can get past it.
0:03:59 > 0:04:03'The crayon just won't budge, so Dr Warren has to go to plan B.
0:04:03 > 0:04:07'Find out later what on earth he's going to do with all that liquid.'
0:04:12 > 0:04:14'And now to our lab. Oh!
0:04:14 > 0:04:17'Where we do incredible experiments...'
0:04:17 > 0:04:18Oh, it's disgusting.
0:04:18 > 0:04:21'..to show you how your body works.
0:04:21 > 0:04:24'Just don't try anything you see here at home.
0:04:24 > 0:04:27'Today's lab is all about fluorescence.'
0:04:28 > 0:04:32Our teeth are going under ultra-violet light.
0:04:32 > 0:04:34Oh, yours are blue. Are mine green?
0:04:34 > 0:04:35No.
0:04:35 > 0:04:38'So what's going on? Well, it's complicated, but...'
0:04:38 > 0:04:42You see light in a spectrum from red through yellow, then blue,
0:04:42 > 0:04:47then violet, and beyond violet is ultraviolet which we can't see.
0:04:47 > 0:04:50But... in our bodies we have molecules that are absorbing the UV
0:04:50 > 0:04:54light from these torches right now and doing something brilliant.
0:04:54 > 0:04:57'The electrons and molecules in my teeth get all excited
0:04:57 > 0:05:01'and when they calm down the release a special light that only
0:05:01 > 0:05:03'shows up when these torches are on.
0:05:03 > 0:05:05'This is called fluorescence.
0:05:05 > 0:05:09'So, in normal light your teeth look like this, but if we lower
0:05:09 > 0:05:12'the light they look like this and that's because the molecules in your
0:05:12 > 0:05:16'teeth are admitting a fluorescent light that you can't normally see.'
0:05:18 > 0:05:21'But something else in your body is fluorescent too.'
0:05:21 > 0:05:24- Aww!- Ugh!
0:05:24 > 0:05:27'Yes, these are escaped splashes of wee.
0:05:27 > 0:05:30'Not very hygienic, but useful for our experiment.
0:05:30 > 0:05:33Best not to try this yourself. We're experts.
0:05:33 > 0:05:36'Some of the waste molecules that come out in your pee also
0:05:36 > 0:05:39'absorb the ultraviolet light and they become fluorescent too.'
0:05:39 > 0:05:42Oh, my goodness, people are being careless.
0:05:42 > 0:05:44Wait, Chris, haven't you been using this toilet all day?
0:05:44 > 0:05:46Xand!
0:05:46 > 0:05:48'So, if wee fluoresces under our UV torches, you know
0:05:48 > 0:05:50'what this means, don't you?
0:05:50 > 0:05:53- 'What? - That your body makes invisible ink.
0:05:53 > 0:05:54'Wow, of course.'
0:05:54 > 0:05:56We're going to do a very special experiment,
0:05:56 > 0:05:58but we're under laboratory conditions.
0:05:58 > 0:06:00Chris, we're in a toilet.
0:06:00 > 0:06:03Look, all I'm saying is we can only do this because we're doctors,
0:06:03 > 0:06:07we're a little bit silly and we're wearing protective gear.
0:06:07 > 0:06:08KNOCK ON DOOR
0:06:13 > 0:06:14'So, now that we've got
0:06:14 > 0:06:17'Xand's wee, it's on with the invisible ink experiment.
0:06:17 > 0:06:20'I'm going to ask Xand three body-related questions
0:06:20 > 0:06:23'and he's going to write the answers in his wee.
0:06:23 > 0:06:26'But we won't see what he's writing because we're about to prove
0:06:26 > 0:06:29'that Xand's wee is invisible ink.
0:06:29 > 0:06:30'It's quiz time.'
0:06:39 > 0:06:42'It's a toughie, this one. Will doctor Xand get it right?'
0:06:44 > 0:06:45I'm done.
0:06:51 > 0:06:54'This is a good question. I know this one.'
0:06:56 > 0:06:59- Are you done?- I'm done now. - Good.
0:07:05 > 0:07:09'Hmm. The amount of wee you produce is very related to how much you
0:07:09 > 0:07:11'drink in a day.
0:07:11 > 0:07:14'That's the end of quiz time.'
0:07:14 > 0:07:16It doesn't look like you've painted anything.
0:07:16 > 0:07:18I have. It's there in my own wee. I did it.
0:07:18 > 0:07:21I know, you've painted in your own urine. That's why we can't see it.
0:07:21 > 0:07:24But if we turn on the ultraviolet light it'll reveal how many
0:07:24 > 0:07:25Xand's got right.
0:07:25 > 0:07:28- There you go.- Yeah, look at that.
0:07:28 > 0:07:30'Now you can see my answers.
0:07:30 > 0:07:32'The molecules in the wee are fluorescing after absorbing
0:07:32 > 0:07:33'UV light.'
0:07:33 > 0:07:37So question one was, "What's the only part of the body that can't
0:07:37 > 0:07:38"repair itself?"
0:07:38 > 0:07:41- Teeth.- Well, actually it's the enamel.
0:07:41 > 0:07:42- I think we'll give you the point. - Yes.
0:07:42 > 0:07:45Question two. What is the body's largest organ?
0:07:45 > 0:07:47- Skin?- The skin is right.
0:07:47 > 0:07:50Finally, how many litres of urine does the average human
0:07:50 > 0:07:51produce in a day?
0:07:51 > 0:07:53I put three.
0:07:53 > 0:07:55Three is wrong.
0:07:55 > 0:07:57The answer is 1.5.
0:07:57 > 0:07:59- So I pee twice as much as an average person?- That's right.
0:07:59 > 0:08:02You probably drink twice as much as the average person.
0:08:02 > 0:08:03Anyway, two out of three isn't bad.
0:08:03 > 0:08:06Let's turn on the lights.
0:08:06 > 0:08:08You can see the writing's disappeared now.
0:08:08 > 0:08:11'So we've shown that molecules in your body fluoresce after
0:08:11 > 0:08:12'absorbing UV light.
0:08:12 > 0:08:15'You've actually got invisible ink inside your body.
0:08:15 > 0:08:18'And this fact was discovered years ago.'
0:08:18 > 0:08:22Urine used to be used by spies as invisible ink to write secret
0:08:22 > 0:08:25messages that could go undetected by the enemy.
0:08:25 > 0:08:28It's still a bit smelly though.
0:08:28 > 0:08:30Xand.
0:08:33 > 0:08:36Now who doesn't love a kick about in the park?
0:08:36 > 0:08:37I know I do.
0:08:37 > 0:08:41Me too, but football can also be a game of danger.
0:08:43 > 0:08:46You could be in danger of pulling a hamstring.
0:08:48 > 0:08:49Straining a side.
0:08:49 > 0:08:52Or even tearing a ligament.
0:08:52 > 0:08:55Ah! Ooh!
0:08:55 > 0:08:58Which is why we always warm up first.
0:08:58 > 0:09:01Do some gentle leg stretches.
0:09:01 > 0:09:03Loosen that body up.
0:09:03 > 0:09:06And make sure those muscles are warmed up a bit.
0:09:08 > 0:09:09There we go.
0:09:09 > 0:09:12I'm thoroughly warmed up and guaranteed to be injury free.
0:09:12 > 0:09:15In fact I'm not just warmed up. I'm boiling.
0:09:15 > 0:09:16Phew.
0:09:19 > 0:09:22Don't need this any more.
0:09:22 > 0:09:25- Oh, my eye! - Oh, no. A minor injury.
0:09:53 > 0:09:56'Put something cold on the eye until the pain is gone,
0:09:56 > 0:09:58'but for no longer than ten minutes.'
0:09:58 > 0:10:02But if you've got problems with your vision go to Accident and Emergency.
0:10:02 > 0:10:04- How's that, Xand?- That's much better.
0:10:04 > 0:10:06I think I'm ready, but hold on.
0:10:06 > 0:10:10PIRATE VOICE: Aargh, I'm going to play in the park with my ball
0:10:10 > 0:10:12until my timbers are shivered.
0:10:12 > 0:10:13Aargh!
0:10:13 > 0:10:17- What are you doing, Xand? - Just thought I'd try option B.
0:10:18 > 0:10:20'So if you get a whack on your eye,
0:10:20 > 0:10:23'put something cold on it for no longer than ten minutes.
0:10:23 > 0:10:25'If you have problems with your vision,
0:10:25 > 0:10:28'get an adult to take you to accident and emergency.'
0:10:32 > 0:10:35Earlier, Courtney came to Accident and Emergency
0:10:35 > 0:10:37after getting something lodged in her ear.
0:10:37 > 0:10:39Let's see how she's getting on.
0:10:41 > 0:10:43'Back in Sheffield Children's Hospital,
0:10:43 > 0:10:46'nine-year-old Courtney has a crayon stuck in her ear.
0:10:46 > 0:10:49'Courtney was in her bedroom with her colouring pens and pencils.
0:10:49 > 0:10:51'She liked the look of the yellow one.
0:10:51 > 0:10:54'"That might fit in my ear," she thought.
0:10:54 > 0:10:55'Ouch.
0:10:55 > 0:10:59'To remove it, first Doctor Warren tried to hook it out like a fish.
0:10:59 > 0:11:01'But never caught a thing.
0:11:01 > 0:11:03'So far the crayon just won't budge.
0:11:03 > 0:11:06'Doctor Warren's decided to call in a colleague
0:11:06 > 0:11:09'who's a dab hand at flushing things out with water.
0:11:09 > 0:11:12- 'Who's that then, Xand? - You'll see.'
0:11:12 > 0:11:14Have we got a towel?
0:11:14 > 0:11:16'Yellow crayons watch out -
0:11:16 > 0:11:19Sister Julie Morcombe's about.'
0:11:19 > 0:11:22'Sister Morcombe's an expert at this procedure.'
0:11:24 > 0:11:27'And don't worry, This isn't painful, it just feels weird.'
0:11:27 > 0:11:30If you just put the fluid in under pressure, then what tends to happen,
0:11:30 > 0:11:34the water flushes behind and pushes the foreign body closer to the
0:11:34 > 0:11:37entrance to the ear canal and then it just comes out with a second go.
0:11:37 > 0:11:40There you go. Out it comes. Pop!
0:11:40 > 0:11:41All done.
0:11:41 > 0:11:44'She came, she saw, she flushed it out.'
0:11:44 > 0:11:47If there's nothing else in behind, then I'll leave you to it.
0:11:47 > 0:11:49Fantastic. Thank you very much, Julie.
0:11:49 > 0:11:52'Courtney's happy she's got her yellow crayon back.'
0:11:52 > 0:11:55We've got it out now. She looks much more comfortable.
0:11:55 > 0:11:57Watch what you put in your ears now.
0:11:57 > 0:11:59'Especially yellow crayons.
0:11:59 > 0:12:01- BOTH:- 'Bye.'
0:12:01 > 0:12:02'Still to come...
0:12:02 > 0:12:04'I learn how we talk.'
0:12:04 > 0:12:05Buh.
0:12:05 > 0:12:07'This girl's bumped her bonce.'
0:12:09 > 0:12:11'And Xand's got guests.'
0:12:11 > 0:12:13That just came out of my ear.
0:12:13 > 0:12:16'That's amazing! And so is this.'
0:12:18 > 0:12:21'An ordinary department store.
0:12:21 > 0:12:24'With an ordinary mum buying some clothes for her daughter.
0:12:24 > 0:12:26'But why's she buying four of everything?
0:12:26 > 0:12:27'That seems a bit much.'
0:12:31 > 0:12:32'Whoa, she's multiplied.'
0:12:34 > 0:12:37'Meet Georgie, Jessica, Ellie and Holly,
0:12:37 > 0:12:42'and as you might have guessed, they are identical quads, four of a kind.
0:12:42 > 0:12:44When they were born, I couldn't tell them apart
0:12:44 > 0:12:47so I drew their initials on their feet with a marker pen.
0:12:47 > 0:12:49'Well that's one way to tell them apart.
0:12:49 > 0:12:52'So what's it like being a quad?'
0:12:52 > 0:12:56I like having my three sisters because I like to play with them
0:12:56 > 0:12:57and have fun with them.
0:12:57 > 0:12:59- 'What do you think, Georgie?' - I love it.
0:12:59 > 0:13:02'Is it always good? is there a downside?'
0:13:02 > 0:13:04They're great, but sometimes they're not.
0:13:04 > 0:13:06'Holly?'
0:13:06 > 0:13:08I can't believe that we had quads.
0:13:08 > 0:13:13'Ellie, Jess, Holly and Georgie are genetically the same person,
0:13:13 > 0:13:16'just like me and Chris, which means they have the same blood type,
0:13:16 > 0:13:18'the same hair colour and even the same DNA.
0:13:18 > 0:13:21'What do you think of that, Holly?
0:13:21 > 0:13:23'But how did that happen?
0:13:23 > 0:13:25'The quads all came along from the same egg.
0:13:25 > 0:13:28'Normally, one egg grows into a baby,
0:13:28 > 0:13:30'but with the quads the one egg split
0:13:30 > 0:13:32'first into two and then those eggs
0:13:32 > 0:13:35'split into four separate babies.
0:13:35 > 0:13:37'But how does mum tell them apart?'
0:13:37 > 0:13:40Their facial features are slightly different and as they develop
0:13:40 > 0:13:43their personalities are slightly different.
0:13:43 > 0:13:46'While Georgie likes eating all kind of different foods...
0:13:46 > 0:13:48'Ellie is a dancer.
0:13:48 > 0:13:52'..Jessica is always reading story books.
0:13:52 > 0:13:54'And Holly is an artist.'
0:13:54 > 0:13:57When other people get to meet them they don't see it straight away,
0:13:57 > 0:13:58but once you get to know them
0:13:58 > 0:14:01you can see that they are quite different.
0:14:01 > 0:14:03'Now that's amazing.'
0:14:08 > 0:14:11'Your body can need mending in all sorts of ways
0:14:11 > 0:14:15'and we're going to meet some special teams that are trained to fix you.'
0:14:16 > 0:14:20Speaking is one of most complicated things you can do, and while I bet
0:14:20 > 0:14:23you know that your lips and tongue and voice box are all involved,
0:14:23 > 0:14:27I bet you don't know what your soft palate does, or even where it is.
0:14:27 > 0:14:30Well, open your mouth and SAY, "Aah."
0:14:30 > 0:14:33Aah!
0:14:33 > 0:14:36See that? It's where the dangly bit hangs from,
0:14:36 > 0:14:38and most of us use it without even
0:14:38 > 0:14:39thinking about it,
0:14:39 > 0:14:42but today we're going to meet a patient who's learning to use hers.
0:14:42 > 0:14:45'Nine-year-old Millie is in speech therapy after
0:14:45 > 0:14:47'she was born with a cleft palate.
0:14:47 > 0:14:48'This means she had a hole going
0:14:48 > 0:14:50'through the roof of her mouth to her nose.
0:14:50 > 0:14:52'She's had a series of operations to fix this.
0:14:52 > 0:14:56'However, Millie still finds speaking a little bit difficult.'
0:14:56 > 0:14:58There are some sounds that you find really easy
0:14:58 > 0:15:01and some sounds that you find difficult.
0:15:01 > 0:15:06I find the S words more difficult than other words.
0:15:06 > 0:15:10- And that's the one you've been working on today, isn't it?- Yes.
0:15:10 > 0:15:11'When you make a speech sound
0:15:11 > 0:15:15'like an S, the soft palate needs to lift up and make a seal with
0:15:15 > 0:15:16'the back of the throat.
0:15:16 > 0:15:19'In Millie's case she isn't able to do that,
0:15:19 > 0:15:21'so when air comes up it isn't directed just into her mouth
0:15:21 > 0:15:23'but also escapes down her nose as well.'
0:15:26 > 0:15:27'To help her with that,
0:15:27 > 0:15:31'she's working with speech therapist Jayne O'Connell.
0:15:31 > 0:15:34'Today I've joined the class and Jayne's set us a challenge.'
0:15:34 > 0:15:37Got to make up a sentence for each of these words.
0:15:37 > 0:15:38I bet I'll be better than you.
0:15:38 > 0:15:42I might use powerful adjectives as well.
0:15:42 > 0:15:45- Oh, you might use powerful adjectives?- Yes.
0:15:45 > 0:15:48I don't think I know any powerful adjectives.
0:15:48 > 0:15:51Saw.
0:15:51 > 0:15:58My dad sawed the wood to make a door.
0:15:58 > 0:16:01'My dad sawed the wood to make a door. Good sentence.
0:16:01 > 0:16:03'Now it's my turn.'
0:16:03 > 0:16:06I saw the sun shining in the sky.
0:16:06 > 0:16:10No that's saw, what you saw with.
0:16:10 > 0:16:11'Millie's having none of it.'
0:16:11 > 0:16:14- So I can't say I saw the sun? - No.
0:16:14 > 0:16:17No, I meant like I saw the... No, that doesn't work, does it?
0:16:17 > 0:16:20- Well, you tried.- I think I need my homework more than Millie.
0:16:20 > 0:16:22SHE LAUGHS
0:16:22 > 0:16:25'There are other sounds that most of us take for granted,
0:16:25 > 0:16:28'but again our bodies have to do more than you'd think.'
0:16:28 > 0:16:30Make a "mm" sound for me.
0:16:30 > 0:16:32Mm.
0:16:32 > 0:16:35What happens if I hold your nose? Listen to what happens.
0:16:35 > 0:16:38Buh. Oh, I can't do it.
0:16:38 > 0:16:41What would normally happen is the air would come down your nose,
0:16:41 > 0:16:43but because I'm holding your nose,
0:16:43 > 0:16:45I'm blocking the air from coming down.
0:16:45 > 0:16:50And it almost turns that sound into a "buh" sound.
0:16:50 > 0:16:51So try that at home.
0:16:51 > 0:16:55Make a "mm" sound, and the "mm" sound is a nasal sound where the
0:16:55 > 0:16:58air does have to come out of your nose, and if you block your nose...
0:17:01 > 0:17:05..you can't make the sound, so it becomes a "buh" as the air escapes.
0:17:05 > 0:17:08'The really difficult thing that Millie's having to learn is
0:17:08 > 0:17:11'to consciously control muscles that most people don't even know'
0:17:11 > 0:17:15exist, like the muscles at the top and the back of your mouth.
0:17:15 > 0:17:17So that is quite a skill to master.
0:17:17 > 0:17:20'Before we finish, Millie's got her own speaking challenge for me.'
0:17:20 > 0:17:23OK, so I've got to say, "Red lorry and yellow lorry."
0:17:23 > 0:17:26- Say it fast.- Fast.
0:17:26 > 0:17:29Red lorry. Yellow lorry, Red worry. Lellow lorry. Red, oh...
0:17:29 > 0:17:31I can't do it.
0:17:31 > 0:17:34'Oh, no, she beat me again. Good luck, Millie.'
0:17:40 > 0:17:43When you get injured, your body is brilliant at mending itself.
0:17:43 > 0:17:46This next boy should know. He's always having accidents.
0:17:48 > 0:17:50# If there's a bone to break he'll break it
0:17:50 > 0:17:52# If there's a knee to graze he'll graze it
0:17:52 > 0:17:55# If there's an ankle to sprain he'll sprain it
0:17:55 > 0:17:57# He's the unluckiest kid. #
0:17:59 > 0:18:02'Food that's gone off or hasn't been cooked correctly can contain
0:18:02 > 0:18:05'harmful bacteria that attack your body.'
0:18:06 > 0:18:08'But your body fights back.
0:18:08 > 0:18:11'Immune cells in your tummy try to kill the bad bacteria.'
0:18:12 > 0:18:15'Oh, watch out! Phew!
0:18:15 > 0:18:19'Then friendly bacteria multiply and release toxins to stop them too.'
0:18:21 > 0:18:24'Then your body gets you to eject them.
0:18:24 > 0:18:27'Sometimes your stomach muscles contract to press them upwards.
0:18:27 > 0:18:29'Or sometimes it's downwards.
0:18:29 > 0:18:33'Your intestines don't absorb water when you have food poisoning,
0:18:33 > 0:18:36'so when diarrhoea kicks in, a lot of liquid is flushed out
0:18:36 > 0:18:38'and you're left feeling dehydrated.
0:18:38 > 0:18:42'So keep drinking water, but not water with bugs in it.
0:18:42 > 0:18:43'Oh, no. Not again.'
0:18:43 > 0:18:47# He's the unluckiest kid. #
0:18:47 > 0:18:48Coming up next, it's...
0:18:51 > 0:18:53Coming up next it's...
0:18:53 > 0:18:54- What are you doing?- Nothing.
0:18:57 > 0:19:00Coming up next, it's Investigation Ouch.
0:19:01 > 0:19:03Gotcha.
0:19:06 > 0:19:09'Now, this place may look like a hairdresser's, but it isn't.
0:19:09 > 0:19:12'They're getting rid of lice.'
0:19:12 > 0:19:15They're very common. I've had them, and no matter what anyone says,
0:19:15 > 0:19:19they're not dangerous and they don't care if your hair's clean or dirty.
0:19:19 > 0:19:21They just love to live in it.
0:19:21 > 0:19:23'You can use special shampoos to get rid of these troublesome
0:19:23 > 0:19:28'parasites, but this girl has come for the five-star treatment.
0:19:28 > 0:19:31'Meet 11-year-old Courtney. What's it like to have lice?'
0:19:31 > 0:19:34I've had them four times, and they're really irritating cos
0:19:34 > 0:19:37you're always scratching your head in the middle of school lessons.
0:19:37 > 0:19:39My mum's always told me not to worry,
0:19:39 > 0:19:41cos you can always get rid of them.
0:19:41 > 0:19:45'That's good advice from your mum. Lice are totally treatable.
0:19:45 > 0:19:48'Before they go any further I'm going to have a look at what we're
0:19:48 > 0:19:50'dealing with face to face.'
0:19:53 > 0:19:56'Crikey! Now they may look icky, but lice are very common.
0:19:56 > 0:19:59'Studies have shown that as many as one in three children are
0:19:59 > 0:20:03'likely to get head lice during the year, so how do we get rid of them?
0:20:05 > 0:20:06'Meet Justine Armitage.
0:20:06 > 0:20:08'she's a head louse's worst nightmare
0:20:08 > 0:20:11'and she's got a rather special technique.'
0:20:11 > 0:20:15We'll hoover Courtney's hair with the specialist lice hoover.
0:20:15 > 0:20:17'Did she say lice hoover?'
0:20:17 > 0:20:19The specialist lice hoover.
0:20:19 > 0:20:20'That's affirmative.'
0:20:20 > 0:20:24For every live lice there is, we'll catch it in the filter
0:20:24 > 0:20:26so we can count how many there are.
0:20:26 > 0:20:28Is it quite fun doing it? Is it quite satisfying?
0:20:28 > 0:20:31Yes, quite mouth-watering when you see lots.
0:20:31 > 0:20:32THEY LAUGH
0:20:32 > 0:20:34'Let's see what we can suck up.'
0:20:38 > 0:20:40'Make sure you get into the corners.'
0:20:42 > 0:20:46'After a thorough treatment, how's Courtney coping with being hoovered?'
0:20:46 > 0:20:47It's nice.
0:20:47 > 0:20:49'She likes.
0:20:49 > 0:20:53'Time to see what Courtney's bonce has been keeping secret.
0:20:53 > 0:20:57'So we've managed to catch several lice and you can see them
0:20:57 > 0:20:58'crawling around in here.'
0:20:58 > 0:21:01So why do lice love hair so much?
0:21:01 > 0:21:04Well, it's warm, it's near a blood supply, your scalp, which is
0:21:04 > 0:21:07what they feed on, and they can also anchor their eggs to hair
0:21:07 > 0:21:09which means they're very safe and well protected.
0:21:09 > 0:21:12Your hair is the perfect environment for head lice.
0:21:12 > 0:21:15'Lice make you feel itchy because they poo on your head.
0:21:15 > 0:21:19'Now that's disgusting but it isn't dangerous, and in fact it's quite
0:21:19 > 0:21:23'useful because it's the itchiness that lets you know you've got them.'
0:21:25 > 0:21:30'Now we've caught the adult lice, but the next step is to find the eggs.
0:21:30 > 0:21:32'A special fine tooth comb is scraped
0:21:32 > 0:21:34'through Courtney's hair to remove them.
0:21:34 > 0:21:36'Let's see how many we've combed out.'
0:21:36 > 0:21:39Oh! You've got loads.
0:21:39 > 0:21:41'One louse can lay 100 eggs at a time.
0:21:41 > 0:21:43'they're also called nits.
0:21:43 > 0:21:45'A week later they'll all hatch into lice,
0:21:45 > 0:21:47'and those lice just keep breeding,
0:21:47 > 0:21:52'so at the end of the month one louse has become 1,000 head lice.
0:21:52 > 0:21:55'Just as well we've got these guys out.'
0:21:55 > 0:21:59- How are you feeling, Courtney? - Fabulous.- 'Absolutely.'
0:21:59 > 0:22:00So that's head lice.
0:22:00 > 0:22:02They're not dangerous, but they are unpleasant,
0:22:02 > 0:22:05but there are other things that live on your body.
0:22:05 > 0:22:06Let's investigate.
0:22:06 > 0:22:09'So, I've come to see entomologist Vince Smith
0:22:09 > 0:22:12'from the Natural History Museum.'
0:22:12 > 0:22:14So Vince, lice aren't the only things that live
0:22:14 > 0:22:16harmlessly on our bodies, are they?
0:22:16 > 0:22:17No, that's right.
0:22:17 > 0:22:20We've also got this other parasite called a demodex mite, and with
0:22:20 > 0:22:26these the older that you are, the more likely you are to have them.
0:22:26 > 0:22:28So let's see if we can find some.
0:22:28 > 0:22:32'Vince is scraping the skin around my eyes to try and collect
0:22:32 > 0:22:36'enough gunk to test, but he doesn't get much, so we go into my ear.'
0:22:36 > 0:22:37There's a good pile of gunk on there,
0:22:37 > 0:22:39so let's see what we can find.
0:22:39 > 0:22:42'I'm sort of hoping he doesn't find anything.
0:22:42 > 0:22:44'Vince is looking through the microscope,
0:22:44 > 0:22:48'and I can see everything he sees on this screen here.'
0:22:48 > 0:22:50You're loaded!
0:22:50 > 0:22:52Ugh, look at that! Ugh.
0:22:53 > 0:22:55- Wow.- It's moving.
0:22:55 > 0:22:58- That's very good. - That just came out of my ear.
0:22:58 > 0:22:59That's fantastic.
0:22:59 > 0:23:03'What does he mean, fantastic? Who is this guy?'
0:23:03 > 0:23:06In the daytime, those mites are living inside the little
0:23:06 > 0:23:10follicles of your hair cells and then during the night-time they
0:23:10 > 0:23:15come out and they're moving around trying to find all their mates.
0:23:15 > 0:23:17So every night there's a bit of a party in my ear.
0:23:23 > 0:23:25So these mites are pretty disgusting,
0:23:25 > 0:23:27but actually they're not doing me any harm.
0:23:27 > 0:23:30In fact, they're useful because they help clean the gunk from your ear.
0:23:30 > 0:23:33We're carrying around all of these passengers
0:23:33 > 0:23:34and this is just the start.
0:23:34 > 0:23:38There are many other human parasites that we've got too.
0:23:38 > 0:23:39'But remember, don't worry.
0:23:39 > 0:23:41'If you ever get lice, it's quite normal and treatable.
0:23:41 > 0:23:42'I've had them.
0:23:42 > 0:23:45'Plus, we all have other little creatures living on us,
0:23:45 > 0:23:47'helping us out with things like the cleaning.
0:23:47 > 0:23:49'Nice work.'
0:23:49 > 0:23:52But they'd better not keep me up all night with their partying.
0:23:57 > 0:24:00Our next patient's had a rather unusual accident.
0:24:00 > 0:24:02Luckily, she's come to the right place.
0:24:02 > 0:24:05- BOTH:- Phew!
0:24:06 > 0:24:10'Accident and Emergency, the place to come for treatment of serious
0:24:10 > 0:24:15'injuries and terrible traumas and, hang on, this one looks all right.
0:24:15 > 0:24:16'Looks can be deceiving, Xand.
0:24:16 > 0:24:20'This is ten-year-old Shannon and she's, well, just listen.'
0:24:20 > 0:24:22My friends was having a snowball fight.
0:24:22 > 0:24:24- 'Right.'- And what I've done is I've backed away.
0:24:24 > 0:24:26'OK.'
0:24:26 > 0:24:28I've slipped on the ice.
0:24:28 > 0:24:30'Well, ice is slippy.'
0:24:30 > 0:24:34I've fell onto a...
0:24:34 > 0:24:37'Onto a...? Hold on, let's get this story straight.'
0:24:39 > 0:24:42'OK. So Shannon was playing in the snow with her friends.
0:24:42 > 0:24:44'She was enjoying running about
0:24:44 > 0:24:46'when the others started a snowball fight.'
0:24:50 > 0:24:52'Oh, watch out.
0:24:52 > 0:24:54'As the snowballs were flying, Shannon backed away,
0:24:54 > 0:24:56'trying to avoid getting hit.
0:24:56 > 0:24:59'Look out for the ice!
0:24:59 > 0:25:01'Yeah, well she didn't, and she went flying,
0:25:01 > 0:25:05'whacking her head onto a big telegraph pole behind her.
0:25:05 > 0:25:07'Oh, so that's what it was. Ouch!'
0:25:08 > 0:25:11'So let's see it then.
0:25:11 > 0:25:14'Oh, that's snow joke.
0:25:14 > 0:25:17'Here's doctor Shorav Munjal to sort you out.'
0:25:17 > 0:25:21All right, Shannon. So what time did this happen?
0:25:21 > 0:25:24'Hmm. Mum? Any ideas?'
0:25:24 > 0:25:26It happened about an hour ago.
0:25:26 > 0:25:28I'm just going to have a look in your eyes.
0:25:28 > 0:25:31'Doctor Shorav needs to give Shannon a thorough examination,
0:25:31 > 0:25:34'but if you're wondering why he's not looking at her cut, that's
0:25:34 > 0:25:38'because the biggest worry after a blow to the head is concussion.'
0:25:40 > 0:25:43'Inside your skull your brain is made up of soft tissue
0:25:43 > 0:25:46'cushioned by blood and spinal fluid.'
0:25:48 > 0:25:50'If your head hits something very hard,
0:25:50 > 0:25:53'your brain suddenly shifts inside your skull
0:25:53 > 0:25:56'and can knock against the skull's bony surface.'
0:25:58 > 0:26:01'When the brain moves about like this it can cause temporary brain
0:26:01 > 0:26:03'injury called concussion.'
0:26:05 > 0:26:09'To find out if Shannon has got concussion the doctor tests
0:26:09 > 0:26:10'how her brain is working
0:26:10 > 0:26:13'by checking her eyes respond properly to light...
0:26:14 > 0:26:16'..her muscles work normally.'
0:26:17 > 0:26:21'And he checks her nerves and finally her balance.
0:26:21 > 0:26:25'Luckily, it looks like Shannon doesn't have concussion which
0:26:25 > 0:26:28'means now the doctor can check out that cut.'
0:26:28 > 0:26:29Quite superficial.
0:26:29 > 0:26:31It needs a bit of superglue to close it up.
0:26:31 > 0:26:33'I'd just like to add
0:26:33 > 0:26:35'this isn't the kind of glue you get at the local shop.
0:26:35 > 0:26:38'It's not superglue. this is special skin glue.'
0:26:40 > 0:26:41'But Shannon's not done yet.
0:26:41 > 0:26:45'Wait till you see what the nurse does to fix that hole in her head.
0:26:45 > 0:26:49'Shannon's own hair is being used as stitching thread.
0:26:49 > 0:26:53'Tying it into knots brings the two sides together.
0:26:53 > 0:26:56'Now that's what I call "using your head".
0:26:56 > 0:26:59'Once the knots are in place, there's a dab of skin glue
0:26:59 > 0:27:01'and it's all over. And someone's relieved.'
0:27:01 > 0:27:02Pop your head up.
0:27:02 > 0:27:05Are you feeling OK?
0:27:05 > 0:27:08- Are you feeling all right?- Yeah.
0:27:08 > 0:27:11'Time to hit the road and head home, but maybe walking backwards
0:27:11 > 0:27:14'is an idea you'll knock on the head in future, Shannon.'
0:27:14 > 0:27:17I would never ever walk backwards, ever again.
0:27:17 > 0:27:19'Best foot forward then, eh? Bye!'
0:27:21 > 0:27:23'Next time on Operation Ouch...
0:27:23 > 0:27:26'Open wide as we find out what it takes to straighten your teeth.'
0:27:26 > 0:27:28She's not very talkative.
0:27:30 > 0:27:33'See what me listening to music has to do with this.
0:27:33 > 0:27:37'And we're mixing up a treat to show you how your stomach works.'
0:27:37 > 0:27:38It looks disgusting.
0:27:39 > 0:27:42Until then, that's all from...
0:27:42 > 0:27:43Operation Ouch!
0:27:51 > 0:27:53Subtitles by Red Bee Media Ltd