Lymphatic System: Crash Course Anatomy & Physiology #44 

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

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

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

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

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)

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!

It's good to know that both me and hank were here because we didn't know what the lymphatic system did

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

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?

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!!

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

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! :-)

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!!!

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.

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

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.

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!

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!!!!!

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

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!

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

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.

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 💜

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

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.

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!

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....

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

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

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

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!

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

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!

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 !

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

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

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

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

I would tell you a joke about salt but Na

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

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

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.

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

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

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

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

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!

awh, baby lymphocyte at 3:09

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

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

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

4:05 I love how the capillaries dance!

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.

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

Here from Hank's latest video where he watched this to learn from himself!

Thank you for subtitles. Helps

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

I subbed, the poor man’s donation

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!

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.

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

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

These videos are great for homeschoolers like myself. Thank you so much for non-crappy education!!!

I love this ! Please do more !

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

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!

Thanks you for this i knew non of this keep making more please.

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!

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

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

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

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

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

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

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.

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.

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.

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

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

Love the animations so funny yet educational!!!!

Excellent demonstration!

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.

Your explanation is extreme sir

Thanks for taking the time much appreciated

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

I've watched Crash Course all through high school and into my higher education.. Hasn't let me down yet!

crashcourse is incredibly helpful! love it

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

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.

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

Lots of respect to your work

"And that's what we're going to be talking about for the rest of this series." Wait, what?! It's nearly over? Awwwwww.

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

Lymphatic System - Great Explaination (y)

Thank you for this video...You actually made learning about the Lymphatic System pleasant as it could be...Much appreciated!!!

Security checkpoints...I love that

What a cool video. Straight to the point.

10 great minutes. Thank you.

Good illustrations!