Circulatory & Respiratory Systems - CrashCourse Biology #27

Hank takes us on a trip around the body - we follow the circulatory and respiratory systems as they deliver oxygen and remove carbon dioxide from cells, and help make it possible for our bodies to function.
Table of Contents
1) Respiratory System 00:48
2) Simple Diffusion 00:55
3) Respiratory Anatomy 02:35
a) Trachea to Capillaries 03:10
4) Lung Function & Thoracic Diaphragm 04:37
5) Circulatory System 05:35
6) Circulatory Anatomy 05:54
a) Left Ventricle to Capillary Beds 06:50
b) Veins to Left Atrium 08:46
7) Endotherms & Ectotherms 09:20
References:
www.khanacademy.org/science/bi...
www.khanacademy.org/science/bi...
www.ideacenter.org/stuff/conte...
This video uses the following sounds from Freesound.org:
"00559 deep breathing 1.wav" by Robinhood76
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[@TheRavenclawTimelord]

Bio final today. Good luck to everyone else who has one soon

[@rochelleleung8680]

exactly

[@traumaticchannah1082]

thanks, i need the luck

[@Faendal91]

Zoology final soon. I hope yours went well.

[@b-dinogianrainierp.8721]

Thanks. :) taking it tomorrow

[@jackarmitage448]

Tomorrow

[@annatatum5434]

The respiratory system is breath taking

[@thepowerful7593]

The circulatory system is heart- stopping.

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The punny guy is in the chat now.

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keeanu reeves

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You made a keanu reference before keanu.........whaaaaat?

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The skeletal system is bone crushing.

[@mrequinox590]

It's depressing how a 12 minute video by these guys have taught me more than 3 years of high-school have

[@alfredsaalo1441]

This guy explains this 10 times faster than my biology techer in school does. This is why you should watch videos on youtube instead of staring at boring powerpoints and writing down notes while getting 5% of what the teacher just said!

[@bobalemonade]

Ikr also i luv ur profile pic :D so cute!!!!!

[@132o4_]

🍳actly LOL see what I did there?

[@notacupoftea]

Alfred Saalo no way! Your teacher actually does their job and teach you? Mine doesn’t

[@shan49618]

agreed.

[@elonmusk8758]

my teacher takes 4 hours just to explain 10% parts of this video

[@x3DaDivax3]

It's so weird, when I watch this I actually like learning... Wonder what my own teachers are doing wrong

[@carysmoroney2854]

Silver Rose Probably because they don't use humour as part of their teaching method. My Anatomy and Physiology lecturer for example has THE WICKEDEST sense of humour and likes to catch us off guard with little jokes and comments to see who's actually listening. It works, let me tell you--no-one falls asleep!

[@bertieclayton4865]

most teachers were probably once like this but the low pay and all the work crushed their spirit and interest in what they teach idk though

[@trcs3079]

I really thought about this and this is my theory; lecturers must meet a quota and guidelines. So for example a class must meet the requirement of 2-3 hours of studying said subject, thus meeting the quota, therefore schools get funding, teachers and lecturers get paid etc etc and so fourth. Thats my theory anyways because my chemistry lecturer teaches in hanks style and usually she explains everything within 10-20mins, whilst the rest of the 2 hours or so shes just elaborating on it or giving out questions for us to answer.

[@theanebrandmuller5799]

They're not teaching me while I'm lying in bed

[@matthewcowell]

I'm a teacher. It's not easy to be as charasmatic as Hank. Can you just 'be' interesting? Some people can, others can't. You can't always pick on the teachers, we try to make it interesting, but it requires a lot more than just a rehearsed YT video.

[@thejrignacio12345]

5:36, for those guys who just needs the circulatory part... you're welcome

[@taumyasomar5964]

I will be forever grateful to you (xD) 😭

[@Garfield7410]

THANKYOU!!!!

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thejrignacio12345 Ah thx chu!! 😂💞

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* need

[@rafipuraditya8425]

All the way t'ill, 9:30

[@aajjeee]

YOU JUST ENTERED MANUAL BREATHING MODE.

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Stop.

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@Asiamah Yaw Nyame =D

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Your tongue feels uncomfortable

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NOOOOOOOO DAMMIT!!!!!!!

[@iphone12i71]

dang it, any instructions on how to switch back to auto mode again?

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Biology test? Biology test.

[@theabdu500]

Biology final? Biology final.

[@Wavgu]

theabdu500 Biology exam ? biology exam

[@thivyaabaskaran989]

+Hannah Liu Screwed Biology ? Screwed biology.

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death ? death

[@sanjakader9011]

+Hannah Liu TFIOS? TFIOS.

[@protoname_]

Hank and John, you guys are saving my junior year

[@SciShow]

CrashCourse Biology always uploads on Monday!

[@dasoyee]

Thank you so much for this! Much easier to follow than my textbook, and since my teacher doesn't actually teach, I guess this'll be how I learn from now on

[@hannahkahrs9132]

This went over the equivalent of like 5 lesson in my biology class.

[@lucywang9445]

You literally covered EVERYTHING on my test!

[@ebonyharris11]

Love these videos! I'm taking online biology courses for school so I do most of my studying alone. These videos are like my "teacher" lol. It sticks with me a lot more when someone else explains it.

[@2013lmm]

Would love a CrashCourse on cardiac output and stroke volume!

[@aidendaniel9812]

Go to crash course anatomy and physiology

[@kailawebb]

I love these videos! The textbook my school has is super outdated and horrible about explaining things. My teacher has no strict curriculum-- he just randomly lectures on something kind of pertaining to the current chapter. These videos are an amazing supplement to my textbook. Hank, have you ever thought about teaching teachers on how to convey information in an interesting way? If the public school system took this kind of organized, quick, and entertaining way of teaching, maybe the US wouldn't be so low on the global educational totem pole.

[@fluffernutter62]

I'm so uncomfortably aware of my breathing...

[@BeautyMarked86]

A video on Blood would be awesome! Covering the formed elements and plasma, and how blood is made and so on. :D Your videos are very helpful!!!

[@jcmontoni9596]

there is one

[@SimraKhadam]

Could you do a crash course on ORGANIC CHEMISTRY

[@NilsKimman]

Im Dutch, so most of the things explained have a different name here, making it more difficult to understand everything. It's still surprisingly fun to hear what everything is called in English. Keep up the great work!

[@ThanhNguyen-nn2ex]

My biology instructor showed this video in the class, and I just can pay attention to it! Great job, Hank! You made me, a student whose English is not his first language, understand it clearly in English without trying translation.

[@VarshiPyndanna]

You are amazing :) Summarised 20 pages in 11 mins and my understanding of the topic has improved!

[@misssilly18]

saw this video in class today kinda had a fangirl moment when i saw Hank haha :)

[@nickkidson337]

Thanks Hank I got an A+ in my Biology examiniation

[@SoleMan117]

Wait a minute, Hank: are you saying the lungs make a total eclipse of the heart?

[@ianna_chia]

god bless this crash course I UNDERSTAND THINGS NOW

[@Blue-ds2bo]

Here because Bio finals are literally in 4 hours !

[@thetechegg8859]

this channel has come a long way

[@Omni0404]

I'd make a terrible doctor, just seeing the little animations is making me queezy.

[@gloriousrobotbunny3275]

watching this was homework, literally xD so cool that i dont have to read about it, thank you

[@HateCrewMTL]

I swear, forget university classes. I might as well stay on your channel and learn. Thank you so much.

[@Meatwadmoney]

Great video sir! Perfect for my middle school students!

[@laurenlancaster1141]

This is fantastic. I think you should maybe do a crash course on internal and external respiration just to fully clear things up. My teacher just confuses me about that... Thanks!

[@alexacheers]

you teach me more than my biology teacher does....

[@laramoshe8295]

This basically summed up my 2 weeks worth of in-class studying on the circulatory/respiratory system in 11 minutes and 39 seconds. i love this.

[@Qladstone]

Watching all crash course videos for the love of learning and knowledge!

[@JaYiSdAbEsT12]

Hank teaches me more in these 10-15 minute videos than my biology teacher does in 5 one hour lessons.

[@ClumsyBum1]

Good luck to everyone here for SAT II Bio tmrw! Keep that hope alive :p

[@catherinesheridan7403]

I love all these crash course videos! Thank you Hank! :)

[@jaylai8462]

In a few hours I have my Bio exam. Thank god Crash Course exist, saving thousand of students

[@meikeandrea]

anybody started a band named 'moist with mucus' yet? Cause I might claim the name now

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You Help me pass My Science Tests!!

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Shut up

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SuperTizianos Any Pro For you if i didn't!?😏😏

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All caps at the start of each word baby.

[@gusluke5191]

thats good!!!

[@juiceislit2986]

Too bad you'll fail English.

[@z3dar]

Every new crashcourse biology reminds me to be amazed that we are alive. It's nice to have most of all necessary things happen automatically.

[@KevinBrennan2010]

This is at such a good level for school. Not dumbed down, not excessively complicated it's Genius!

[@sparkleandshine2494]

You are now my bill bye the science guy to help me ace my biology exam you are a life saver I love crash course ♡

[@Saad-rm8sd]

+Sara Marie Same here xD

[@chloebutler8438]

Bill Nye of the 21st century

[@clavonne89]

Hank is the MAN!!!!

[@PatrickKrebsH]

It is really cool how all of the body systems work together to get stuff done. I am not a huge science expert so I always just thought that the Circulatory and Respiratory systems etc. all just functioned independently. Thank You CrashCourse!

[@vatnidd]

This is just amazing. These videos pretty much summed up weeks of lessons in a less-than-15-minute video!

[@salahm8029]

once again hank's saving my ass at bio class....... Crash course, I salute you

[@sarahprice9090]

Bio final tomorrow. Thanks for the help. x

[@madisonrose_official]

You're like a happy, caring Sheldon Cooper :)

[@vye6737]

I just wanna say that this series has helped me so much! Between Science Olympiad and wanting to test out of Biology, I needed to find study material that works. This has been one of the only ones I've found. Your videos are so funny and informative, and I've learned so much--more that I ever could of thought! So, thank you!

[@andrewjames2294]

Am i the only one having a hard time breathing while watching this video? 😂

[@juiceislit2986]

Yes

[@quillchristhomas5311]

These videos are great! Can you guys make Anatomy and Physiology videos that cover this and more about the human body?

[@Epac818]

Friggin love this channel player

[@jonathanwelch2371]

This dude is brilliant! Thanks for the work you put in.

[@assumingcougar]

U da real mvp

[@SapientSpaceApe]

You pronounce "capillaries" strangely.

[@takeastepback1689]

I noticed that it was different from the way it's pronounced in London. Kept concentrating on the word for a bit too long. Oh well, the content of the video's good.

[@SapientSpaceApe]

Agreed. Crash Course is amazing. In fact, I was watching the Chemistry playlist when I received your reply.

[@GeorgiaEllen130]

British vs. Americans

[@fmar105]

Sounds normal to me.

[@daaaniphantom]

Georgia Sinclair wait if they are british why does John Green sound super American?

[@laceyblue4752]

I would not be passing biology or psychology without you hank, you're "fracking" awesome!!

[@WhereThingsComeBack]

Videos like these make me so grateful just to have working lungs, a heart, and, well, everything else. I know you're trying to educationize me, Hank, but you're also making me feel feelings and thankfulness. Boo.

[@mango9865]

Learning through videos make me more interested through a particular subject, especially biology. Although some of the syllabus are quite different with the Malaysia student syllabus, but it's good for me to learn more. Continue your hardwork! Really appreciate.

[@xhanetan5204]

Hai, from Malaysia

[@CHARrrrrrrrr]

Must. Not. Keep. Staring. At. Mole.

[@heropreacher3760]

Lol!🤣🤣

[@noahlebovitz2879]

Hey Hank! Thanks for another wonderful lecture, in the table of contents at the end, it says veins to left atrium where it should say veins to right atrium!

[@danbram999]

Mate you deserve a medal, you've taught me more than all my lectures put together! Thank you!

[@uchihadonaru469]

I got my results and I did really well because of you guys! thank you so much!

[@rumiahmed1494]

YES I KNOW THIS IS BIOLOGY... BUT YOU KNOW WHAT I WANT... A VIDEO ON PRIDE AND PREDJUDICE BY CRASH COURCE.

[@DrPhysiophile]

Another one going out to my Anatomy and Physiology class! Thanks, Hank.

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Studying for my DAT in 7 days and my laptops hard drive blew up. I lost every note from college, the $700 program i bought, and all the test prep questions I had. CrashCourse has been my best friend.

[@nyxmabery8954]

This could really help someone that is working on a science project like I am

[@jmunt]

3:35 he SAID a fifth of a millimeter (which is equivalent to 200 micrometers), but the diagram shows 50 micrometers. 200 micrometers is indeed the correct average diameter of alveoli, so I'm guessing the diagram is trying to show the diameter of an individual sacs within the alveoli. In case anyone was wondering. Probably just me though.

[@masterlillyclaw]

+Jarrett Munton In the video he says that each individual alveolus is 50 micrometers, not an entire alveoli.

[@minipt13]

my bio teacher showed us this during class. I was so proud to have already seen the video :)

[@lauz9234]

Great video. I actually learned something.

[@majesticfirearc]

"Eloquent question. Well asked!" That is, unfortunately, how many of my questions are phrased :P

[@carolmaldonado2503]

"Moist with mucous... Another great band name" :3 Oh... Hank lol

[@TakayakiGal]

This guy is brilliant! Sooo much simpler and a lot easier to listen to! Thank you xxx

[@meganlove4494]

This channel has saved my life a million times this year.

[@jessicaweiler9160]

Hank is so cute, I love his little side jokes.

[@b1lly_b0bz35]

you talk so fast but somehow I can remember what your saying :)

[@kaveverythingnerd324]

Thank you so much for doing this Hank, it is really helping me calm down as I get ready for bio final.

[@flowerpowerocks3283]

the masters of detailed summarising!

[@issacstalclose9988]

Bio tests today and tommorow... Wonderful -_-

[@907babyblue]

i feel ya

[@issacstalclose9988]

+Hadeel Elshak So god damn boring, I finished it 10 minutes in and was bored out of my mind for the other 20 minutes. Why??? It's FIFTEEN MULTIPLE CHOICE QUESTIONS! I'm not autistic!

[@FardinKhan-nk5ep]

Update: there are 700 000 000 or 700 million alveoli in both of the human lungs as per the new research results. Thank me later.

[@JesusFreakMusak]

I would not be making it through IB Biology without Crash Course - THANK YOU!

[@stuttersomthing]

Man, this is so helpful for my anatomy class at the moment, we just started Respiratory System. Thanks Hank! :D

[@meredithbayona5762]

Is it only me or Hank looks sad?

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Poor sad boi

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bc he is sad look what he made a vid on

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Yep. Every animal needs a heart... Unless you're a sponge 😂😂

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I love these, me and my school use this for everything! Thank you so Crash Course! You're the best for everything, for learning, or just for fun!

[@hannahl7142]

THANK YOU SO MUCH FOR THIS SERIES! I am SO SCARED for my bio honors test and this has calmed me down a bit

[@sahilmalhotra2750]

to answer your question at 2:00 hank. yes! yes i do want to be constantly moist xD and for everyone out there thinking it, yes i know.. that's what she said. now grow up! lol

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Sahil Malhotra noice

[@radhika5802]

2.05 im moist right now and regret nothing

[@amromelhim4979]

+Radhika Doraisingam she means she is wet

[@rjmayo]

Thank-you sooo much for talking about these topics together, when I first learned the basics of them I was taught one, then the other and got confused.

[@hbaldecchi]

Taking the SAT Bio test on Saturday and you have saved me so much time trying to decipher whats in my book. THANK YOU THANK YOU HANK

[@ScoutaIoo]

Yo know, when i was watching this i just realized how insane this is. I don't mean that offensively, this is fascinating but seriously stop and think about how fucking weird we are, bags of meat and tubes stuffed into a sack and held up by lumps of collagen. I know most people here already heard this but each time i come to this realization the more it blows my mind. This is why i love science.

[@skyofstorms]

Cool to see fellow bronies in the comments of non mlp related vids. I've been finding a lot more of us as of late. #BroniesFTW

[@silentbitbeadly8652]

This is what I needed for my test on "Circulatory and Respiratory Systems". Thank you Hank keep up that awesome. PS grate robot tone at the beginning. (^ o^) LOL!!!

[@juiceislit2986]

Burn

[@SkywalkerAni]

The lungs are amazing! I remember learning about them in my Environmental Toxicology class, and the way they're set up to take in Oxygen and keep out bad things is amazing.

[@ABooleanEarth]

I think this is my favourite episode of Crash Course Biology so far. It has the best writing.

[@ChancingYT]

A lot of you are old studying this. I am in 5th grade and we are learning this.

[@ChancingYT]

IllusiveCookie Lol ok. You do that ;)

[@ChancingYT]

IllusiveCookie And uhh, is pissing off a thing?

[@frostbittenfire]

You aren't going into nearly as much depth into the topic.

[@levonwoodward3321]

+DialgaPVP good one you cuz im in grade 3 and im a geenius -6 times -4 equals 24

[@frostbittenfire]

Dominique T. No, as a matter of fact, you're not. In all honesty, do you really believe an elementary school class would go into the same depth as a high school level course?

[@NabaaYousif0_1]

Before watching the vid: I’m so confused so I won’t lose anything After: how can something be so confusing 😅

[@Bushki1]

I was not expecting Hank to appear but it made this 100000000x better that he did :D

[@Shaitaniyat]

You, Dear Sir, are just amazing.