Lymphatic System: Crash Course Anatomy & Physiology #44

Hank describes the structure and function of your lymphatic system and how it supports your cardiovascular and immune systems. He'll explain how your lymphatic system collects, filters, and returns interstitial fluid back into your bloodstream, and how your lymph nodes and lymph organs activate your immune system to fight off infections.
Pssst... we made flashcards to help you review the content in this episode! Find them on the free Crash Course App!
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Chapters:
Introduction: Airport Security 00:00
The Lymphatic System Structure 2:09
Origins of the Lymphatic System: Capillary Beds 3:12
Lymphatic Vessels 3:47
What Does the Lymphatic System Do? 5:05
Lymph Nodes 6:04
Mucosa-Associated Lymphoid Tissues (MALTs) 6:59
Review 8:04
***
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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

[@papyrusted]

THANK YOU SO MUCH!!!!!!!

[@crisharrell]

Thank you so much, that’s awesome!!!! 😊😊

[@PizzaShrimp]

Awesome

[@gldsundrp9087]

When I’m rich Imma start donating. We need to protect Crash course at all cost lol

[@amandaputman4476]

Notes from the video in case anyone wants them Lymphatic system Quitely plays a vital supporting role to both your cardiovascular and immune systems Maintains homeostasis by eventually returning most of the fluid that has been diverted back into your blood Three main parts Lymph- watery solution does not contain red blood cells, which remain in the closed circulatory loop because they are too large to pass through the capillary membrane Lymphatic vessels help to reabsorb fluid Lymph nodes- monitor and clean lymph as it filters through Tonsils, adenoids, thymus, spleen Lymphatic capillaries Lymphatic capillaries are all over the body except for bones, bone marrow, teeth, and CNS Lymphatic capillaries made of loosely overlapping endothelial cells that look like roofing shingles- forming flap-like valves that only open in one direction When the pressure in the interstitial space becomes greater than the pressure inside the Lymphatic capillary the flaps push and open and take fluid in to relive the pressure Once the fluid inside a lymphatic capillary it is now lymph Ducts The right lymphatic duct drains all the lymph collected from the upper right area of the torso as well as the right arm and the right sides of the head and thorax and feeds them all into the internal jugular vein Thoracic duct takes lymph from the rest of the body and dumps it into the subclavian vein They operate under very low pressure Have a series of valves that prevent backflow and are helped along by smooth muscles Edema or swelling that can constrain blood flow Lymph nodes Lymph nodes house T cells that directly attack invaders and manage the immune system, b cells that secrete antibodies into the blood, macrophages that eat up foreign substances, and reticular cells that make up the stroma scaffolding network that supports all other cells in lymphoid tissues Internally each lymph node is divided into distinct cortex and medulla regions: the outer cortex houses dividing B cells, while its deeper areas contain mostly T cells. Lymphocytes Lymphocytes are found in and mature in the loose reticular connective tissue that makes up a large part of the nodes and most your other lymphoid organs The medulla contains both types of lymphocytes Release macrophages and activate the general immune system MALTS Mucosa Associated Lymphoid Tissues (MALTS)- found in mucous membranes around the body, outside the lymphatic vessels Tonsils some of the largest collections of these tissues which together form a ring around the entrance of the pharynx. Where they can inspect everything you eat and breathe They Try to remove any pathogens before they enter the GI tract or lungs Peyer’s Patches- in the distal portion of the small intestine Appendix - contains a bunch of lymphoid tissue to destroy any bacteria before it can breach the intestinal wall during absorption

[@augustinusskovgaardchriste3004]

Hank Green is a national treasure. Beat that cancer, buddy.

[@angeline_1994]

You will be my saviour during my time in nursing school! I just need to get used to watching these more often (I only come here when I have exams coming up lol)

[@ajluke92]

Resa Elle same! I have a bioscience exam tomorrow so this is my cram session 👍🏼

[@gorgeous3325]

Resa, totally! I'm pre-nursing as well, and I do the same. That's actually a really good suggestion. Instead of coming here just to cram, we should review all the BIO series in their entirety in my spare time just to really familiarize myself with the systems and physiology.

[@gorgeous3325]

BTW, is that Pac?? I love it! Whatcha know about 2pac? lol. It's crazy when I listen to a 2pac song that references the year and I'm like, "OMG, that was over 20yrs ago! How did that happen?!"

[@maxreaper25]

OtterBabs I find it difficult to become familiar with this material by only watching videos. Honestly

[@wayvislife]

LOL this deadass me...

[@arundhatisubhedar7163]

Could we have a Crash Course series on various diseases that affect the human body?

[@Zaisoomi]

YES PLEASE!!!

[@biancadesilets2285]

Check out Dr. Robert Morse, I think he has the best understanding on the diseases of the body and the lymphatic system :)

[@abdul-rasheedraheem140]

GoingT

[@gracebiggers9688]

Just wanted to say, I find these Crash Course videos incredibly helpful for learning about the immune system. You guys are just so good at really explaining things well and are better at helping me to visualize these concepts than a textbook is. Keep up the good work!

[@Talifax]

Heard the news and had to check up here to remember what was going on! Stay well, Hank!

[@gorgeous3325]

Many *commenters say Hank speaks too fast.* That makes it a "Crash Course" & is perfect for review, but if you wanna *_slow it down to soak up info_* that's complex or new to you, *_click the gear in bottom right corner, click speed, click 0.75._* Many know this, but some don't. Hope I helped someone out! Can I get a thumbs up?

[@debbiewilkins2624]

Thank you for that but I am looking for the gear but I don't see it. Where exactly is this at? Also, I wonder why we can't reverse it like other clips on KZbin from other people.

[@cnb1243]

Debbie Wilkins it’s the the three dots in the upright corner 🤗

[@gordonjin2791]

He sounds drunk

[@domenick9542]

You are the fooking mannnnn!!!!

[@Ashley-ew7dp]

Turning the captions on can also help :)

[@Windkisssed]

That was a fantastic presentation. I have been in medicine the majority of my life and that tops any lesson I've ever had! Both informative and as always, fun to watch. Thanks for sharing with the world! Lauri

[@NovasYouTubeName]

We use your videos for homeschool all the time and they are fantastic! I learn along side my 3 kids! Will donate this month! Thank you!!

[@adventuresinfreezedrying]

As someone who has had Primary Lymphedema for the last 30 years, there is more information in this video on Lymphatics than what most doctors know and understand about the Lymphatic system...Thanks for helpting to educate people on their Lymphatics and why they are so important!

[@laurenpoole2035]

Love the comparison of the lymphatic system to security! It's funny how a simple analogy can make information that seems overwhelming more relatable and less daunting. Thank you! :-)

[@jonathaneleven2265]

Crash Course, I just want to say to keep the good work! It helps me a lot (especially chemistry), and it'll be a shame if it stops, I appreciate the content you make.

[@crashcourse]

+Jonathan Eleven Thank you! Glad we could help and that you're enjoying it :D -Nicole

[@ryanpius5873]

Agreed :)

[@shonna79]

For someone who found out there Lymphatic system was the reason they have been debilitating sick I appreciate these videos more than anyone will ever know. It took 2 years of neck pain, multiple diagnoses and sick with every thing you could get the whole time. PEOPLE NEED TO REALIZE!!!

[@ajones7713]

Just want to express how much I appreciate these videos. Shoutout to Hank for always keeping it interesting and comical

[@Shispirito100]

I'm brazillian and love this channel, I've learned so much things that I have not seen in my High School, Thank you so much for it 💜

[@kierstenworkman9962]

These videos are helping me through nursing school. THANK YOU!!!

[@Meryem-fb7tn]

I'm from Germany and you're my saviour. No one has such amazing animation in german youtube nor the capability to explain. Thank you Sir!

[@redcoat4348]

when i was little, one of my teachers wore a glove on her hand. I asked her why and she explained that twenty years ago she had cancer and the treatment required that she remove one of her lymph nodes. [insert explanation of lymphatic system] and that since the lymph node wasn't there to let through lymphatic fluid, it flowed down into her hand make it swell without the glove. i would explain this to other kids when i discovered my interest in speaking

[@EnragedSephiroth]

Amazing. Like this episode.

[@redcoat4348]

EnragedSephiroth sarcastic or?

[@EnragedSephiroth]

No, seriously my mind was blown. This is a system I know little to nothing about.

[@redcoat4348]

EnragedSephiroth ok. they don't remove lymph nodes anymore.

[@fooloutinthestorm5438]

+Jeffy Samuel Well, they took one of mine out to make sure I actually had cancer, but it sounds like the rest will be done just with chemo (and maybe radiation).

[@No0o279]

The host is awesome and the animation makes the course that much more easy to understand as well as keeps your mind from wandering elsewhere.

[@stressedoutazim3931]

awh, baby lymphocyte at 3:09

[@Esb1120]

real g!!! Im in tears after this whole week studying for my intro bio class. This is the last video I'm watching for my test tomorrow, and it's really helped me! thank you so much!!!!!

[@mollykraemer9852]

These videos helped me pass Human Anatomy, Microbiology and probably will help me understand the first half of Immunobiology next semester. Thanks Crash course!

[@YolaroozXD]

I understood more about the lymphatic system in this 9 minute video than in two of my biology teacher's 50 minute classes. Gj Crash course, gj.

[@thejollydwarf2275]

Seriously giving me the ability to graduate Highschool with these online classes since the COVID-19 caused my schools to close down. Thank you!

[@teaoliver2512]

You guys are amazing and are a resource I recommend to all my friends! Please never talk slower, speed is what makes these videos great.

[@exceptionalprogression3763]

This is easily one of the best series anyone could ever use to get a good start in their studies for Anatomy and Physiology I & II. Thank you very much Crash Course

[@jessicamariposa6726]

I am so inspired, grateful and motivated by Crash Course! Hank, Thought Cafe and all of you hard working, talented individuals who script, design and help deliver this information: You're seriously changing my brain in all the best of ways. Thank you so much, I will gladly contribute to your cause.

[@chels5126]

I listen BEFORE my teachers lecture and i feel like i can grasp things so much quicker. THANK YOU

[@kjj9]

I have Klipple Trenaunay Weber Syndrome and Lymphedema, a malformation in my lymphatic system which caused me to be born with a swollen right light which eventually worsened as I got older to the point where my toes started discharging a lot of lymphatic fluid and blood non-stop along with a lot of pain and it's still something I have to deal with today at 27. Throughout my life my doctors never properly explained to me what I had so I had to research everything for myself. Actually, my doctors SUCKED! They told me to do things that actually made my condition worse since they didn't really know how to treat it themselves and didn't think to refer me to other doctors that might know how to help me. I'm managing it the best I can now but I want to learn more information about my condition so I can manage it more effectively. Thanks for uploading this. I'm gonna watch all of these videos.

[@elizabethmaas3907]

BRAVO! I enjoyed Hank's unsung lymphatic system immensely, a great refresher course and learning tool to pull together stuff I had and have yet to learn! Excellent job!

[@crisharrell]

I absolutely love Crash Course! I’ve learned so much from you and have had fun doing it! The humorous way that you present the materials is such a refreshing, stress relieving way to approach learning. Thank you guys at Crash course y’all rock!!! Please keep the videos coming....

[@ForrestHarstad]

This is just tremendous edutainment. Crash course rocks! I see many say the talk is too fast. No! The speed of the talk is wonderful. It's faster than reading, thanks to the marvelous graphics. (Just stop if you miss something, back up a touch, and you'll inevitably find a word you don't know the definition of. Look it up and then this speed is better than slower.) And one can find the short segment one seeks very readily. Hats off to Crash Course!

[@manastalksessions1053]

This guy is just amazing! Thank you for this Crash Course you completely Rock!!!!

[@drumchode]

You're amazing at what you do. Thanks for breaking the mold of typical educators.

[@HiThere-yy8zk]

4:05 I love how the capillaries dance!

[@rosemarietolentino3218]

I have been looking at a bunch of videos on the Lymphatic System. And your video is the most informative one I have seen. Thank you!

[@laurakeepax8744]

Thank you for your wonderful series. I am using this series in my class to reinforce the immune system. My students love your work!

[@guillemiami]

One of the best youtube videos I've ever seen. Thanks.

[@ainsleysdelusions]

I love how before I watched this series I thought that your spleen was useless, I can learn so much from you hank

[@Jess-pr1xf]

I'm a nurse, but prior to watching this; the lymphatic system seemed to me like magic. Thank you for bringing it back into the realm of science.

[@alainaz7713]

I am in an introductory food nutrition class, and this series has saved me so many times!! I only took high school biology, so thank you! I understand it so much better now.

[@anishmaparajuli7496]

Thank you so much for making my work easy..................... I just love your videos and there is fun in learning with your videos being provided :) Cheers !

[@hussamashfaq8624]

anishma parajuli Hey

[@judybrown8070]

Amazing explanation of the lymphatic system, very well delivered. Thanks for sharing.

[@mizzsmith8415]

Thank you for subtitles. Helps

[@singinwithceline]

As someone with Lymphedema, I greatly appreciate this video. Thanks Hank!

[@jessicaluciafloresgonzalez4519]

Really helpful. It truly inspired me to keep learning!!!

[@johneshak640]

Great work .... very very helpful to understand complex subjects in short period of time

[@puremadness6856]

Lymphatic System - Great Explaination (y)

[@waqasbutt7248]

+Pure Madness A representative told me sometimes that happens if your liability is exactly equal to the money in your account. Try reducing your backer's stake by 1p, it should work and won't make much difference.

[@waltonvirk7670]

I’ve always seen match betting on these type of guides but never really looked into it but evidently you can make a fair bit.

[@rickeytfranks9386]

+Pure Madness It might be worth your while contacting them to clarify things. I’ve also noticed a huge drop in the amount

[@annabelly5272]

awesome man !

[@nabeelbossboss9929]

+Pure Madness . Matched betting means that you win whatever the outcome... Remember you only lose the liability and not the stake amount if you lose on Betfair.

[@charliebradley1340]

FUUUUUN!! I needed this review, it's been over 20 years since college and I have had a lot of patients with lymph issues lately. Thank you!

[@sagnikbala2638]

I am watching these from 2019 and it always cleared all my problems

[@YouGoGlenCoco97]

Thank you Hank and Crash course team! This video was really helpful and educational

[@Anniekaaria23]

One of the best clear, understandable videos. Thank you!

[@sagnikbala2638]

Your explanation is extreme sir

[@lemonadethefifthp389]

Thanks! I was having a bit of trouble with this topic in Biology class. This video was really helpful.

[@simranjoharle4220]

I am glad that i found this channel.........the amazing Graphics and a teacher like Hank makes learning fun............thank u crash course

[@martinasera825]

People say you talk too fast. But i think you should never slow down. I always sleep in slow talking lectures and sometimes have to put the speed at 1.25 but crash course you have done it for me. Thanks a bunch

[@sour4704]

cheers and thanks to hank while he still made lots of CC videos, and for educating us on tons of material. and also for sci show and vlogbrothers.

[@herpsenderpsen]

the "police organs" of the body are definitely the most amazing systems we have in my opinion.

[@minhkhangtran6948]

+herpsenderpsen Unlike the TSA however... which make this example really ironic

[@Jus10Ed]

+herpsenderpsen I like how absolute (enthusiastic?) your immune system is. Fun fact: You have an antibody to destroy the saliva of everyone you have ever kissed on the lips.

[@herpsenderpsen]

Jus10Ed nice, i'll tell that to the next person trying to kiss me :)

[@herpsenderpsen]

***** yes i agree with you, in the human body there is no conflicts between the different motivations of cells and bacteria. They do what nature has always done: adapt to their surroundings. The bacteria does not care if it's in some way "held hostage" by a multi-cellular organism, as long as they survive as a specie. The fact that cells have adapted to live for doing certain "tasks" and in return gain advantages just show how extremely complex nature is, and it's all done without someone ever asking an organism what it would prefer.

[@medusaairsoft265]

ķnj

[@YSLQueen]

i have a test on this friday! PERFECT TIMING CRASH COURSE!

[@isaacmiranda8686]

Im a brazilian student, and omg! Even for me that dont have a fluent vocabulary could understand the class. This helped me better than a bunch of pdfs and old videos that i have. Thank u a lot.

[@sarac5360]

Thank you for this video!😊It is greatly appreciated!

[@MsLikki1]

just paused the video to say thank you so much for making these videos! my Bio teacher is so boring and hard to understand so I'm watching your videos to help me understand my notes and prepare for the exam. thank you!

[@MS-vz7pg]

Excellent demonstration!

[@DJAFUNGANG91]

Hey Hank! Thanks again for another great crash course lecture.

[@LowScoville]

This is my favorite system :) my anatomy instructor called it the shadow of the cardiovascular system. Before that, I took physiology and didn't think much of it, I only thought that it handled the fats from the GI tract. I've since learned so much more by taking immunology and hope other people grow to like it as much as I do.

[@AIReStudios]

Great introduction! Had me lured right away! Amazing educational video :)

[@maestroh2986]

Your videos are the best - fun, informative, and lots of pictures.

[@mcse404]

perfect video. Thank you !

[@evelynfuentes2371]

thank you !!! the video was very helpful for my terminology class :)

[@uumhafsachanel737]

You made me understand everything I had a project for this thank you very much

[@clemensquinones4863]

Thank you so much Sir & your team!

[@JoJelliBean]

THANK YOU! This video was posted just in time for me to study for my test tomorrow. I was having trouble understanding the exchange of fluid. I wish part 2 were here already but I'll take what I can get!

[@M_Chen333]

+JoJelliBean There is no part 2; next time it'll be Immune system part 1...

[@courtneyjeffery8262]

Thanks for taking the time much appreciated

[@robm6726]

These Videos are a great help, I wish there were some for my Mircobiology course. They are a big help for visual learners like me.

[@larrybryant2631]

Really appreciated, Hank! Haven't IGNORED the importance of taking care of my lymph system since graduating nursing school in 93'...

[@alyssamsipe9123]

Am I the only one who gets distracted by moving objects and the slushing liquids on the desk?

[@alyssamsipe9123]

Danii Koehler hahah sorry. They jiggle around with his hand movements

[@alyssamsipe9123]

Kassidar I get what you're saying, but I really don't think I have autism. I get daily chronic migraine so my attention isn't always the best, especially if I'm in the postdrome stage of one.

[@jackdon7589]

+Alyssa Sipe i noticed it the first time i saw crash course lol, it is distracting

[@zoearonoff9247]

+Kassidar lol that's kind of a big jump. poor attention is a symptom of a million different things, not just autism.

[@jackdon7589]

^^

[@antd6208]

Seriously this guy is Amazing.. I love how clear he is and how his animation makes it helpful to understand. GREAT STUFFF MON

[@selcouth516]

Thanks! I used your info for my presentation in school

[@bykiaralee]

Amazing timing, really.

[@pavanwalde]

Lots of respect to your work

[@user-sl2gj3pb4g]

Omggg I literally have an anatomy exam on this tomorrow thanks this helped

[@nicodasm]

10 great minutes. Thank you.

[@jena_r8178]

I like your speed, I understand well and I'm not tired of watching🤩👏🏻

[@siinasirotw]

crashcourse is incredibly helpful! love it

[@Nusrah008]

Just in time for my final this month! Thank you :)

[@emmelineduong]

I adore all of your videos... thank you so much! Keep up the beautiful work! :)

[@hanafaizah9485]

Finally the lymphatic system! My biology exam is in a week's time and this is going to help me so much! Thank you Crash Course team!

[@dwiki001]

thx. helps a lot

[@Disnutzz]

thank you so much for this. God bless y'all

[@jujoo1237]

I love this ! Please do more !

[@aviel3361]

Awesome video!

[@Ladycyberella]

How fascinating!

[@christinaoxo]

I love this video, I will probably watch it 4 more times because you talk so fast.

[@ggonsg]

Thank you so much. You're AMAZING!!

[@MegaDrMC]

I just learned this in class last week! Thanks for the refresher Hank, made it a lot easier to understand. :D

[@fadibhae5118]

U bcme a doc now

[@goose2411]

Thank you for the help

[@grauekatze]

I am a lymphatic drainage therapist... this will be an excellent way for me to check how much I remember of the theory. good job so far.

[@ChloeClive]

Fantastic video.