Pratica di Shadowing: The Real Reason Why You Have Allergies - Impara a parlare inglese con i video

Creazione lezione...
1
If you're a fan of our work, you probably value rigor and humility in research and are willing to change your mind based on new information.
2
You might also appreciate the same principles applied to important questions like: "How can my donation make the biggest impact?" GiveWell, this video's sponsor, does precisely that.
3
They publish all of their footnoted research along with their past mistakes, for free.
4
More details, including how to get your donation matched, at the end of this video.
5
An allergy is like finding a spider in your bedroom and exploding a nuclear bomb.
6
Sure, spiders are upsetting and now dead, but so are all of your neighbors and your dog.
7
You can be allergic to an incredibly diverse and weird amount of stuff: pollen, dust, insect stings, animal hair, any kind of food, latex and even your own sweat.
8
One of the wildest things about allergies is how fast they are, breaking out suddenly and violently.
9
And you can develop new allergies.
10
One moment you're enjoying a shellfish you ate thousands of times before, and the next moment you wake up in an ambulance.
11
A shrimp can kill you.
12
How bizarre!
13
But, like, what are allergies?
14
Why do our bodies flip the table on harmless stuff?
15
There's a wild and interesting idea we want to share with you.
16
Humans might have created allergies by accident by getting rid of worms.
17
For your ancestors, being infected by worms was a reality of life.
18
We won't get into the disgusting details, but in a world where drinking water and our poo were close buddies, some species of worms found just the perfect cycle of life.
19
They enter your bodies with the water and make themselves at home, sometimes for decades, and then release their eggs or larvae with your poo, which used to go back to the water we drank.
20
So, until recently, in evolutionary terms, our ancestors had to deal with frequent or permanent worm infections.
21
This caused all kinds of unpleasant health effects.
22
Our immune system had to find weapons to get rid of them.
23
But how do you do that?
24
From the perspective of a cell, worms are cities-scale kaiju reaching beyond the horizon.
25
Worse, instead of skin, parasitic worms have an elastic protective layer that withstands even stomach acid.
26
You really need to pack some punch to cause damage.
27
It takes an army to kill a worm.
28
We're simplifying but, basically, when a worm enters your body for the first time, intelligence cells notice their presence.
29
They move to your lymph nodes and activate specialized antibody factories called "B cells".
30
We explain them in detail in this video.
31
These B cells are told that they need to fight parasites and start producing a special class of weapons, IgE antibodies tiny protein crabs with two pinches that connect to worms like magnets to metal.
32
IgE floods your entire body and basically begin arming a nuclear bomb, an army of really scary cells called "mast cells".
33
Mast cells are huge bloated fellows filled to the brink with histamine and other nasty chemicals.
34
They pick up the IgE floating around and cover themselves with them like angry Hedgehog Grenades without their safety pins.
35
And then they just lie and wait, angrily.
36
So now you have millions of bombs, in your skin lungs or gut.
37
Until the day the mast cells meet a worm trying to enter your body.
38
There's not much time to get rid of it so things escalate rapidly.
39
The mast cells with their IgE spikes grab onto the worm particles and… kind of explode.
40
They release all of their dangerous chemicals all at once.
41
A few things now happen in rapid succession.
42
First, some of the mast cell chemicals wound the worms, ripping wounds into them and making them really unhappy.
43
Then emergency chemicals like histamine cause massive and rapid inflammation ordering your blood vessels to flood the battlefield with water to flush the worms out.
44
They also order your cells that make mucus to go into overdrive and cover the worms in sticky slime.
45
Other chemicals are like air raid sirens, screaming loudly throughout your body for anti-parasite soldiers: eosinophils.
46
First thousands, then hundreds of thousands hear the alarm leave your blood vessels to where the mast cells are causing inflammation.
47
Not only do they make the inflammation worse, they carry extremely toxic chemicals that they vomit at the worm, ripping open its defensive layer and causing horrible injuries.
48
Sometimes this will straight up kill the parasite.
49
Lastly the anti-worm coordination cell arrives: the basophil.
50
It makes sure that the immune system doesn't slow down but keeps attacking with violence.
51
It keeps the inflammation going and alerts more and more attack cells to the sight of battle.
52
Zooming out, we see that the chemicals from your anti-parasite forces make your smooth muscles contract rapidly, pushing everything that's inside, outside.
53
In your intestines, combined with all the water, you notice this as diarrhea.
54
as your body tries to expel the stressed parasite.
55
In your respiratory tract loads of mucus and water flood outside trying to take the worm with them.
56
If this happens under your skin, your tissue is red, hot and itchy as your immune system is trying to commit murder.
57
It takes a fierce army to kill a worm and your anti-parasite forces have the license to act rapidly and with intense violence.
58
Okay, this is nice and all, but what does all this have to do with killer shrimps?
59
Parasitic worms don't love being ripped apart by millions of bombs, and as all living things do, they adapted to the deadly attacks on them.
60
In a nutshell, worms release a plethora of chemicals to manipulate your immune system.
61
They make it weaker and much less angry like immune system weed.
62
Which is pretty bad for your survival because you have to fight off all sorts of intruders every day.
63
Our ancestors were basically unable to prevent regular worm infections, so, as the worms adapted to us, our bodies had to adapt to them.
64
To balance out any weakening worm chemicals, one adaptation might have been to make our immune system more aggressive so it could still defend against other invaders.
65
And then, a hot second ago in evolutionary terms, everything changed.
66
We suddenly invented soap and hygiene but, most importantly, the separation of poop and drinking water.
67
This destroyed the life cycles of parasitic worms and the ones that remained were eradicated by modern medicine.
68
Worms still infect up to 2 billion people, mostly in undeveloped rural regions or slums with unsanitary conditions and dirty water.
69
The people who escaped these conditions now face an interesting problem.
70
An immune system without a major enemy that had kept it down for millions of years.
71
It could very well be that our immune system still operates assuming that worms are making it weaker, and that it has to be overly aggressive because of that.
72
And while IgE, mast cells, basophils and eosinophils also have other jobs, a major reason for their existence has now gone away.
73
But they kind of act as if worms are around, only that they now attack other dangerous foes, like shrimps.
74
This is exactly what happens when you have an allergic reaction to a shrimp.
75
Your immune system picks up shrimp proteins and produces IgE antibodies against shrimps.
76
The antibodies then arm mast cells, turning them into bombs.
77
So you have millions of bombs in your skin, your lungs or your gut with a license to choose violence, even when provoked a little bit.
78
Until one day you eat another shrimp, your anti-parasite forces flip on like a switch.
79
Only there is no kaiju to attack.
80
This is what you experience when you have an allergic reaction.
81
Extremely powerful weapons now target your own body.
82
Under your skin, your blood vessels suddenly turn leaky.
83
Fluid streams into your tissue, your skin swells up and turns red, often in itchy hives.
84
You immediately feel hot and unwell.
85
In your digestive system, the mast cells can cause nausea, cramps and sharp pain as water floods into your intestines and triggers intense diarrhea and vomiting.
86
Your respiratory tract swells up making breathing hard.
87
Way more dangerously, histamine and other chemicals can cause the smooth muscles in your lungs to tense up.
88
In the best case, you get a stuffy nose.
89
In the worst case, you're suddenly fighting for your life.
90
Mast cells all over your body unload their bombs all at once, causing an anaphylactic shock.
91
Your blood loses so much water that your blood pressure drops to dangerous levels.
92
This alone is life-threatening.
93
In combination with the things going on in your lungs, anaphylaxis is a life or death emergency, often with just a small time window to do anything about it.
94
Allergic reactions truly are no joke.
95
Even the deadliest diseases like Ebola need days to kill you, but your immune system can kill you within a few minutes.
96
And this is why a shrimp can kill you.
97
Because, on a fundamental level, an ingenious defense system, vital for our species survival for millions of years, is fighting imaginary kaijus.
98
Yet we still don't know why some people produce a lot of IgE antibodies against certain substances and others don't.
99
We don't know why some adults develop new allergies later in life or why some allergies disappear over time.
100
And we're not sure if the lack of worms is the main culprit, only that the cells that evolve to fight them are responsible for the symptoms of allergies.
101
There are other ideas, like less diverse microbiomes or increased pollution.
102
Maybe it's just a combination of all of them.
103
But what we clearly see is that allergies and their more serious cousin, autoimmune diseases, have been rising massively in the last 100 years.
104
Wherever humans moved into more sanitary conditions and got rid of some of the horrible parasites hunting us.
105
Hopefully we'll figure it out and prevent allergies forever Because one thing's for sure: we don't want to get worms back.
106
That would really be like finding a spider and exploding a nuclear bomb.
107
GiveWell wants as many donors as possible to make informed decisions about high impact giving.
108
They have now spent 17 years researching philanthropic opportunities and direct funding to a few of the highest impact opportunities they found.
109
Over 125,000 donors have used GiveWell to donate more than $2 billion.
110
Rigorous evidence suggests that these donations will save over 200,000 lives and improve the lives of millions more.
111
You can find all of their research and recommendations on their site for free.
112
If you've never used GiveWell to donate, eligible donors can have their donation matched up to $100 before the end of the year or as long as matching funds last.
113
You can make tax deductible donations to their recommended funds or charities and GiveWell doesn't take a cut.
114
To claim your match go to givewell.org and pick "YouTube" and enter "Kurzgesagt" to checkout.

Vocabolario e note di pronuncia per questa lezione

Questa lezione di conversazione di livello C1 si basa sul video “The Real Reason Why You Have Allergies”. Le parole che ritornano più spesso: worm, cell, mast, immune, chemicals. Questo video contiene 114 frasi e 1840 parole da ripetere con lo shadowing. Il parlato dura 11:09. Chi parla ha un ritmo naturale di circa 165 parole al minuto, vicino a una conversazione quotidiana. Solo il 76% delle parole rientra nelle 3.000 più comuni dell’inglese, quindi il lessico è impegnativo.

Vocaboli chiave di questo video

Le 15 parole più avanzate del video, con pronuncia e significato:

ParolaPronunciaSignificato
worm sostantivo/wɝm/verme
mast sostantivo/mɑːst/albero
allergy sostantivo/ˈæl.əɹ.d͡ʒi/allergia
shrimp sostantivo/ʃɹɪmp/gamberetto
antibody sostantivo/ˈæn.tɪˌbɑ.di/anticorpo
donation sostantivo/doʊˈneɪʃən/donazione
inflammation sostantivo/ɪnfləˈmeɪ̯ʃən/infiammazione
allergic aggettivo/əˈlɝ.d͡ʒɪk/allergico
ancestor sostantivo/ˈæn.sɛs.tɚ/antenato, ascendente
histamine sostantivo/ˈhɪstəmiːn/istamina
explode verbo/ɪkˈsploʊd/esplodere
donor sostantivo/ˈdəʊnə/donante
adapt verbo/əˈdæpt/adattare
eosinophil sostantivo/i.əˈsɪnəˌfɪl/eosinofilo
intestine sostantivo/ɪnˈtɛs.tɪn/intestino

I phrasal verb che sentirai

ParolaSignificato
pick up verbotirare su, sollevare
break out verboevadere
go away verbopartire, andarsene
slow down verborallentare, decelerare

La grammatica di questo video

Le strutture che chi parla usa di più, con le parole esatte del video:

StrutturaNel video
Forma passiva be + participio passato — conta ciò che accade, non chi lo fabeing infected · are told · being ripped
Present perfect have/has + participio passato — un’azione passata che conta ancora adessohas now gone · have now spent

Pronuncia a cui fare attenzione

Chi parla usa 15 contrazioni e forme ridotte, come don't, you're, doesn't. Pronunciale nella forma breve, così come le senti.

  • I suoni “sh” e “zh”: shrimp /ʃɹɪmp/, donation /doʊˈneɪʃən/, inflammation /ɪnfləˈmeɪ̯ʃən/, evolutionary /ˌiː.vəˈluː.ʃən.ɛɹ.i/, specialize /ˈspɛʃəˌlaɪz/
  • Parole lunghe — attenzione all’accento: antibody /ˈæn.tɪˌbɑ.di/, inflammation /ɪnfləˈmeɪ̯ʃən/, parasitic /ˌpæɹ.əˈsɪt.ɪk/, eosinophil /i.əˈsɪnəˌfɪl/, diarrhea /ˌdaɪ.əˈɹiː.ə/

I suoni difficili per chi parla italiano:

  • /h/ — va soffiata, non è muta: histamine /ˈhɪstəmiːn/, humility /hjuːˈmɪlɪti/, hygiene /ˈhaɪˌd͡ʒiːn/, harmless /ˈhɑɹmləs/, unhappy /ʌnˈhæpi/
  • Consonante finale — senza aggiungere una vocale dopo: mast /mɑːst/, shrimp /ʃɹɪmp/, allergic /əˈlɝ.d͡ʒɪk/, parasitic /ˌpæɹ.əˈsɪt.ɪk/, explode /ɪkˈsploʊd/
  • /æ/ — più aperta della “e”: allergy /ˈæl.əɹ.d͡ʒi/, antibody /ˈæn.tɪˌbɑ.di/, ancestor /ˈæn.sɛs.tɚ/, parasitic /ˌpæɹ.əˈsɪt.ɪk/, adapt /əˈdæpt/

Come esercitarsi con questo video

  1. Ascolta tutto il video una volta senza parlare e annota le parole che non conosci.
  2. Inizia a velocità 0,75×, fai shadowing frase per frase e torna alla velocità normale quando diventa facile.
  3. Registrati e confronta con l’originale, facendo attenzione a parole come worm, mast, allergy.

Cos'è la tecnica dello Shadowing?

Shadowing è una tecnica di apprendimento delle lingue supportata da studi scientifici, originariamente sviluppata per la formazione dei traduttori professionisti e resa popolare dal poliglotta Dr. Alexander Arguelles. Il metodo è semplice ma potente: ascolti un audio in inglese di madrelingua e lo ripeti immediatamente ad alta voce — come un'ombra che segue il parlante con un ritardo di solo 1–2 secondi. A differenza dell'ascolto passivo o degli esercizi di grammatica, lo shadowing costringe il tuo cervello e i muscoli della bocca a elaborare e riprodurre simultaneamente i modelli di discorso reale. La ricerca dimostra che migliora significativamente la precisione della pronuncia, l'intonazione, il ritmo, il discorso connesso, la comprensione dell'ascolto e la fluidità del parlato — rendendolo uno dei metodi più efficaci per la preparazione alla prova di speaking dell'IELTS e per la comunicazione reale in inglese.

Tecnica dello shadowing: leggi la guida completa passo dopo passo →