Respiratory System, Part 1: Crash Course Anatomy & Physiology #31

So we all know that breathing is pretty important, right? Today we're going to talk about how it works, starting with the nameless evolutionary ancestor that we inherited this from, continuing to the mechanics of both simple diffusion and bulk flow, as well as the physiology of breathing, and finishing with the anatomy of both the conducting zone and the respiratory zone of your respiratory system.
Pssst... we made flashcards to help you review the content in this episode! Find them on the free Crash Course App!
Download it here for Apple Devices: apple.co/3d4eyZo
Download it here for Android Devices: bit.ly/2SrDulJ
Chapters:
Introduction: The First Air-Breathers 00:00
Simple Diffusion 2:44
Bulk Flow 3:59
Mechanics of Breathing 4:30
Anatomy of the Conducting Zone 5:47
Anatomy of Respiratory Zone 7:07
Review 8:33
Credits 8:56
***
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Thanks to the following Patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:
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[@crashcourse]

Pssst... we made flashcards to help you review the content in this episode! Find them on the free Crash Course App! Download it here for Apple Devices: apple.co/3d4eyZo Download it here for Android Devices: bit.ly/2SrDulJ

[@nathanaelzsatish4045]

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I love your app. It has helped me supplement my studying so much. I can understand the text after your videos. Also, you're information is easier to digest than my teacher. I'm not sorry.

[@unknownerror169]

@@mysticore Settings > playback speed > 0.75x. And the analogies are great.

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Who has an exam tomorrow 😂😂

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Me

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today for me

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Stop attacking me

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Mee😬😂😅😭😭

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Next week me

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What a breathtaking video.

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+RogerRoids you did not just....

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:)

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(sigh)

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+RogerRoids Hey! Puns are my department.

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***** Holy crap that's so freaking profound :O

[@robscallon]

I'm so conscious of my breathing while watching this

[@jensharald9091]

OMG Rob? What a coincidence. Big fan! Did you have a test the next day or? :D

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Well I don't become conscious of my head banging while watching ur videos...

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LMFAO

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me too

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Lmao rob wtf are you doing here

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I've just recently quit smoking cigarettes and watching these videos makes me feel so happy to be smoke free

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I gotta give credit to you, Crash Course, for helping me pass all my science tests.

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honestly

[@indiadavies1370]

same

[@indiadavies1370]

We even watch them in class sometimes, their great!!

[@stylez521]

meanwhile, using as revision for anatomy in university :P

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Oxford Univееeersityyyу Revеаls: Quick Insоmniа Curе => twitter.com/6b32c5ac996d61862/status/804614583075733505 Rеspрirаtоrу Sуstеm раrt 1 Crash Coursе А P 31

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I have problems concentrating and making myself study... essentially I couldn't do it. Until these videos... thankyou for making educational videos that are done in an engaging and friendly way : ) Things like this are the only way I can study. : )

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Anybody here watching this for an online school assignment while in quarantine cuz of COVID-19?

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Totally me.

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yup

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Nah just watching cause I’m curious

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Yep lol

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Haha me

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Okay but really, this channel is the only reason why I passed my Anatomy and Physiology class.

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This was even helpfull for me, a university med-student, I have been reading 3 anatomy and physiology litteratures in order to learn everything, then you came with this video making me understand almost every important concept in a fun and easy way ! you deserve a lot of credits ! love ur channel, and here you get one more subscription !

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+Vractomorph wow where did that came from and why are you writing this? do I know you?

[@vractomorphable]

Mahmoud Nijim learn to speak English before fucking with me. It's "where did that come from" not "where did that came from". Would have thought koran would educate you better.

[@fatherofjustice1073]

***** My English is completely fine. No one is fucking with you, don't be naive.

[@fatherofjustice1073]

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K

[@chainman624]

I’m watching this 1 hour before an exam…….. 😅

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The only reason I still have hope for my future is because Crash Course exists.

[@IceNixie0102]

6:24 I'm pretty sure that sharing the throat for breathing and swallowing IS IDEAL, as anyone with a bad cold can tell you. It's really, really good that we aren't restricted to ONLY breathing with our nose and swallowing with our mouth. Like really good. We'd all be dead.

[@adamedengodlandscaping9085]

Its amazing, how intelligence is necessary to understand how all this works, but not necessarily to develop the system itself.

[@TimberWulfIsHere]

its ironic tbh

[@Rationalthinke4r]

you know.... All this complex, integrated, and functional development that happened to occur randomly. But If I claim that a factory exploded in the middle of no where, and please don't ask me where this factory comes from, and after millions of years I told you that in the rubble I found a perfectly functional rolex (against the second law of thermodynamic) would you not look at me like I'm crazy. Do you know much more complex one simple cell is in comparison to the finest rolex. But they'll teach this foolishness as fact and call you a religious nut or fool if don't believe it. In some countries you can't even receive a high school diploma if don't believe in this forced foolishness.

[@mrconch7238]

not an appropriate comparison at all. Biological/evolutionary processes have the ability (so to speak) to 'throw out' forms and functions which do not work. More importantly, forms and functions which do work are kept. Also, its billions of years - a number large enough you (and I) cannot really comprehend.

[@TimberWulfIsHere]

Matt Contreras it's not comprehendable because it's not true, there is overwhelming evidence against the belief of millions of years. Millions of years also do not bring new functions or traits in all species, natural selection and mutation can only use information that is there or remove information.

[@mrconch7238]

I wasnt talking to you originally, I was speaking to "rationalthinker". Millions of years is not a "belief": its a conclusion based on observation and evidence. Otherwise I'm not sure I understand what you are really talking about as it's not articulated very clearly, sorry.

[@medjed2511]

why doesn't oxygen learn parkour then it can get over the obsacles easier

[@soratsuki469]

because science

[@joshrelatedstuff]

It's called collateral ventilation mate ahha

[@hadeslives.1402]

@pansy He is a PUBG player... Parkour jumping is nice there... You wouldn't know that

[@ratsofatso1015]

True tho

[@UzumakiNaruto-ez8jc]

The second he showed the diaphragm I started to voluntarily breathe.

[@sion8]

Me too! I have always wondered why do we have control of our breathing while also being involuntary, yet not of our heart beats? Both are needed to life but we can stop breathing voluntarily meaning not that much O2 while that happens.

[@RockSprites]

Uzumaki Naruto Just goes to show how susceptible our minds and bodies are to suggestion.

[@Timka09]

sion8 I think it's because we need to be able to temporarily stop breathing when we're submersed in water or surrounded by smoke. You don't have complete control of your breathing though, you can't hold your breath for too long for example. There isn't any reason for us to have such control of our heart rate, none that would have made it more likely for our ancestors to reproduce anyway.

[@RockSprites]

Well, when considering heart rate -- it can be regulated by will and thought. It is advantageous in certain situations to control heart rate. Fear and anxiety help us in survival situations, but too much fear/stress can be harmful and prevent us from solving problems. So, regulating breathing and heart rate are useful in other ways, right?

[@Timka09]

RockSprites Our nervous system control the heart rate involuntarily much better than we would do voluntarily. Or it would if our lifestyles didn't change so rapidly in the past few thousand years (or maybe tens of thousands). The human population didn't have enough time or selective pressure to adapt to these changes. Besides, when it comes to stress and anxiety it's better to control the hormones in your blood rather than directly controlling your heart rate.

[@wisperone11]

Thanks! Your videos have proved priceless when teaching my EMTs. It makes it so easy for them to understand. They are fun and full of so much info. Now that you have the apps, I have sent that info onto my class to help them study for their EMT Class

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THE HUMAN BODY IS AMAZING!!!

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How I Cured My CаndidaLife-long Suffеrеr DiscoversPPoweееrful Sеeecrеt Tо Yеаst Infеction Freedoomtwitter.com/d8b09f36b2ffa21ee/status/784262969735516160 Rеespiraааtоry Sуstеm рart 1 Crаsh Cоurse А P 31

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Shut up kid go cry to mummy

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@@estonianmapping2282 worst joke ever

[@MysticNessly]

Learning this in the classroom, I got pretty much a solid understanding of all this, but paired with the graphics you provided really helps to see how these systems intricately work together. Makes you appreciate life more. FASCINATING stuff

[@myratariq6869]

I LOVE HANK GREEN HE'S THE BEST

[@z2u]

Myra Tariq i agree - i think he is the smartest of the bros

[@InternationalCoco]

+z2u How about Hank and John are both really good at different things. Like Hank knows science and John knows history and literature. No need to compare them.

[@cablecar10]

***** You just did compare them

[@adamkadda8803]

kek

[@DUANEYAISER]

Thank you so much Hank Green and the whole Crash Course, you are my favorite teacher of KZbin. Here's my general process of working with your (mainly chemistry, biology, and anatomy) courses: watch each video several times, read on the same subject in one of my science books, lather, rinse, repeat. I'm 20 years out of school but have never had the total understanding then as a student of these subjects then as I do now. Learning for the love of it is so much more effective than rushing to take it all in for the next assignment, quiz, or exam, and that it what your courses help me do.

[@Hyperian]

thumbs up if you were breathing consciously the entire video

[@kevinnguyen7554]

Why do you ask that?

[@donaldtrump1923]

Kevin I agreee y ask

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@@kevinnguyen7554 do I know u????😂

[@Xxtapator]

Fx_ Vetniss No

[@ivyvetniss3148]

@@Xxtapator your name is Kevin nyguen I know a someone with that name

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I keep getting set extra work by my science teacher because I'm enthusiastic and this channel has allowed me to do really well in the research. Thanks to this channel I get to participate in a science day for g+t pupils on Tuesday! x

[@daniellecoutinhorodrigues1059]

Hank, your videos are being extremely helpful! They motivate me to keep on chasing my goals by working hard at my studies. Thanks a lot, and congratulations for your amazing work! Best regards from Brazil. :)

[@jerrinm7691]

When did the big bang theory and theory of evolution go from being theories to facts?

[@misasoupu]

Woww this is my favorite Crash Course A&P episode yet!! It made me laugh multiple times while simultaneously making sense of what hours of studying did not! Thank you so much, as always! :)

[@gingerbihhh]

how has this dude not been honored by SOMEONE. THIS GUY HAS HELPED ME IN LIKE EVERY SUBJECT

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as soon as I graduate & get a job I will become a patron, these videos are saving my life

[@alewiina]

Once again Hank, you've saved my grade. It never fails to amaze me how you explain this stuff so much clearer than my prof lol.

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Was trying so hard to focus on the video but that “evolution” lecture killed me

[@6568754]

The fact that I can listen to this man all day dammmnnn hes a handsome man with a nice voice :P

[@DeepikaSharma-jx4wi]

What wonderful graphics and such an amazing way to explain the difficult concepts about the human body. Thankyou for your video. Just a small request - I wish you could speak a tad bit slower though. The information was moving too fast to take it all in.

[@marchenkogirl]

You got me through Chemistry and both of my A & P classes! Thank you forever!

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🎇❤🎇✨🎶🎆❤💖💘💛💌💍👎👎👈👈✊🙅🙏🙋🙋👯🙍🙆🙁😍😍☺😩🙂🙂😄😄😅😉😋😆😄🍑🍎🍌🍈🍅🌽🍧🍭🍧🍣🌵🌵🍂🚘🚘🚘

[@jriceblue]

Just going to say: that was one of the best introductory sequences Crash Course has filmed. ...Yes, it was a long one (2:35?) ...but it was worth it: colorful, illustrative, informative, and entertaining. (...and well-read. ...and well-illustrated!) Kudos.

[@djkwikkut]

Best way to supplement studying. Very thorough, helpful, and you make it easy to understand with examples and animations. I've used crash course videos for microbiology and now anatomy and this helps me get a's

[@flaminghawk5369]

There wasn’t a second of that video where you weren’t talking, really helped thx

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omg his hair looks so much better than his earlier videos lol

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1:16 Magikarp!!!

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yay!

[@PeaceEcho_]

YAY

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Simp

[@leahfuss7271]

Than you Hank for creating such hilarious and educational videos for the Crash Course Series! For those individuals who find science boring, or difficult to understand; your humor and casual approach engages the non science crowd and allows for actual learning!

[@paulafrengul9761]

Your videos help me visualize the material I learn in class! You are an amazing teacher, thank you so much!

[@MrKariman]

Absolutely interesting! Thank you for the quality!

[@omnithis9214]

2:34 just only the intro??!!!

[@_sampadamishra]

A sweet fast and good 9 minutes video teaching amazingly the very boring chapter of human physiology. Thanks! ❤

[@mollsgreys5827]

He makes everything sound SO dramatic!!

[@edwardnorton5617]

Love crash course, but this was a frustrating one. Reviewing for exam you don't need the first evolutionary half and had to play at .75 speed for the last bit it was covered so quick. Still interesting and great content

[@nouramuhammad2583]

who else watching this cuz u got a test coming up?!?

[@henrybartaby2001]

yeah me

[@fynnolson6939]

ME

[@christina4282]

Thanks man,my teacher explains in the most complicated way possible. But you use your own words and it was easy for me to comprehend.

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I just found this amazing channel and it helps me a lot for my science exam..... thank you!!!! 😻

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wow, i'm early! this course has been a favourite of mine so far on crash course!! :)

[@Nekotamer]

NO NO NO you dont mess with magikarp. mine has tackle . imagine a 10kg fish tackling you. you dont want that scaly rigid body on your face at tackle velocity. respect magikarp.

[@cs889201a]

plus it evolves to gyarados

[@ratsofatso1015]

Hail the naked eye

[@cs889201a]

@@albabimam1114 just sayin a powerful pokemon evolves into another powerful pokemon fun

[@BeingTheNerdIAm]

omg, you not only made it entertaining, but super informative and easy to understand.. Thank you Crash Course!

[@mahmoudsallam8675]

this channel is very useful i watch the anatomy and histology videos as an introduction to my main course in the faculty of veterinary medicine

[@paolay.9722]

I’m really scared to take my final

[@maarmartins]

this is the first time I have ever watched a video at 720p (because my Internet sucks that much)... this is an amazing part of life and now I'm just sad because I'm probably never going to watch a video with that much quality any time soon :( anyway, greetings from Portugal!

[@jjer125]

your life sounds exciting !

[@daedra40]

+jer125 jer125 I don't understand your comment...

[@daedra40]

+Maria Dias This sounds pretty saddening.. You can bet I'll be hoping (if hope can do anything, then let's hope so! :P) that your situation will evolve sooner, rather then later.. A good internet speed will be a great investment by any sovereign power for their people as people like you and me are so easily able to enjoy the dispensing of knowledge! In the mean time, it's super kickass to hear you spent your first time watching a HD video on KZbin was on crashcourse. That's a real achievement in my books :D

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+jer125 jer125 I'm not sure y u commented that

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Maria Dias that is actually heartbreaking to hear; 1080p must seem like a myth to you then

[@brandycostello5541]

I love these videos! They are fun and engaging while learning. I truly appreciate the information. Great Stuff! Thank You!

[@kayceemorgan1614]

I love the knowledge we learn from these videos, but man the sense of humour is one of the best qualities

[@blackmesa232323]

Man, this took my breath away. I now find it hard to breathe. I this is now my pulmonary source of information.

[@mariahstout552]

Thank you crash course for helping me understand human anatomy for my college classes!

[@Srky6P]

Breathing actually has a lot of things to do with amblyopia, a neurological disorder that shuts down one of your eyes. With basic stretching of your nostril on your weak side you get big improvement. I don't if that's a solution to amblyopia but it definitely helps. Our brain only takes one side of oxygen, try it for yourself, you only breathe through one nostril.

[@jademondia6568]

LITERALLY A LIFE-SAVER! THANK YOU, HANK & JOHN GREEN!! ♥

[@inessagud]

Am I the only one who skipped like the first minute of the video, because I don't believe in evolution? God is so good. Takes a mastermind to create something like this.

[@LittleKidGaming]

Crash Course, please do a video on the muscles. Thank you.

[@VendanCorl]

You guys need to do a series for applications of this course (i.e. First Aid, EMT, CPR, etc.)

[@julese5115]

Don't think I'm not grateful, because I am. Truly. These videos are basically DIVINE in terms of studying.... like an animated Bible for science nerds ... But do you think you can do a video on respiratory volumes and capacities? I know it's probably too late and you've moved on to other things but that would be awesome. It's a pretty big section in A+P 2. My semester is almost over but I think it could really help future students

[@SeamusMcMichael]

I LOVE CRASH COURSE!! ❤️

[@kellygriffin54]

Love these videos. They are great for my anatomy class, even the lecturer uses them.

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I always thought crash course was full of useful information but too fast to catch most of it until I discovered how to slow down the speed :) now they are perfect

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Thank you this helped me with my project

[@haleylu2440]

These videos are saving my life, and my grade, in anatomy

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Your information helped me pass my science project

[@lordoffacts]

Really great videos. Well explained, informative and entertaining.

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This video really helped me for my upcoming test !!!😃 Thanks😀😀😀

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I really enjoy your videos. I am getting back into school after almost a 20 year break and your animations are Awesome!!

[@derekzhaosvlogchannel7240]

stop scrolling through the comments and concentrate

[@theodoruhl5423]

this has made me really aware of my breathing

[@naughtyleopard21]

I feel I'm entertained and getting educated at the same time. :D Very great videos!

[@moonchild7094]

Look the heart looks like a heart in shape 💜💜💜

[@RegularOnlineID]

This makes me appreciate my lungs!

[@xanderj3843]

Really thanks man I needed to know this for my biology test thank you very very mutch!

[@kate28bravewatermelons84]

oh blimeeeey. we are already through with this system... but thanks for providing such videos. i hope there would be history of science :) as well more Anatomy and Physio

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Who has an final exam tomorrow 🙌🙋🙋 me lol love these videos 💖

[@esiuol360girl19]

Brilliant!! But awkward that im watching this to help understand my University assignment haha fantastic video

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Thank you Crash Course.... Now I can stop having a tutor... I can study with vids now!!!

[@QT5656]

I love the fact that crash course isn't afraid to mention the very basics of extensive evolutionary research and comparative anatomy.

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I`AM FROM COLOMBIA AND I SEE YOUR VIDEOS EVERY SINGLE DAY YOU POST ONE

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im part of the crash course comitty, oh ya ya oh ya ya

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This resource is exceptional. Thankyou.

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I am so glad I subscribed to crash course right now!😁

[@0IO]

dum pig

[@kellywu6266]

1:17 lol the magikarp

[@Minty1337]

magikarp!

[@come2fahad]

Bro u saved my life thank u so much , may u be blessed in every aspect of your life this helped me a lot

[@ghadeer5049]

From an iraqi pharmacy student , thank you very much 😢❤❤❤

[@SpicyAir]

I've been pronouncing alveoli as al-vio-le, like ravioli

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me too lmao

[@davidndiulor8428]

Al-vee-oh-lie

[@QT5656]

Congratulations - you're British! 🎉 👏

[@Elle-on5pz]

Lol at the Magikarp reference at 1:16

[@bharatastro2513]

JUST LOVE your videos. Keep up the good work!!!!

[@Mazzawak]

Great video as always, but if you want to talk about mechanisms that prevent food from entering your respiratory system you should concentrate on the vocal cords more than the epiglottis, because they do most of the job. In fact the epiglottis is so secondary that we can pretty much live without it (with more difficulty but eventually people without epiglottis get the hang of it...)

[@ChibisOnTheLoose]

"Share a common ancestor" Couldn't it be a trait that multiple organisms evolved, like carnivorous plants did?

[@GWT1m0]

THE CREATIONIST ARE COMING! - Every crash course A&P video

[@MrRenoo94]

lol well that's another theory that works

[@josephang9927]

Creationist may be wrong, but You are the idiot here.

[@zour5]

Man that brobaron guy seems to really hate tests or something.

[@GWT1m0]

Joseph Ang *****​ Wow, are you guys seriously so butt hurt ? But what I said there was a *JOKE* to lure in the "What ever I say is true, I don't give a F**k" people here and Who in their right mind would use "THE CREATIONIST ARE COMING" as a rebuttal to any of the comments in this comment section ?! Thus, please, chill out, somethings in life are to be taken seriously but something as stupid as somebody posting about something that you don't like shouldn't be taken seriously...

[@SScarletUTPB]

+brobaron Evolution is a scientific theory. Creationism is a religious philosophical idea. This is settled in courts in the US. It's like fulminology is a science which tries to find natural (non-supernatural) reasons for lightning. "Thor causes lightning by striking his hammer with an anvil" is a religious or philosophical idea. Both have reason and evidence which could be presented. Sorry - you just seemed to be equating the two as if they were the same.

[@Lucardini]

Darnit, I had a redo end of year exam about this earlier today and now it comes out?! :( still it did make me understand it even better, thx guys! :D

[@gretchenfischer8160]

thought i had seen all these bio/physiology kind of videos but WOOT not this one. i feel so powerful. Thanks AGAIN Hank. You Rule. Because of you (oh. and me) I'm gonna be the nursiest nurse that ever nursed. yes i subscribe cuz: Yea You. love, gretchen.