The Immune System Explained I – Bacteria Infection

  • Published: 01 July 2014
  • Every second of your life you are under attack. Bacteria, viruses, spores and more living stuff wants to enter your body and use its resources for itself. The immune system is a powerful army of cells that fights like a T-Rex on speed and sacrifices itself for your survival. Without it you would die in no time. This sounds simple but the reality is complex, beautiful and just awesome. An animation of the immune system.

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    Why you are still alive - The immune system explained

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Comments • 24 397

  • Kurzgesagt – In a Nutshell

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    • martijns ark15
      martijns ark15  4 days back

      Ill prob buy something soon i love ur content its both educational and fun to watch😀

    • Shega Desta
      Shega Desta  1 months back

      Can you make part 2 for the other cells

    • Karma
      Karma  1 months back

      Kurzgesagt – In a Nutshell son una secta?

    • leon springer
      leon springer  2 months back

      Ich liebe es!

    • sally kilby
      sally kilby  2 months back

      Hi Kurzgesagt .The information is great, like the way the graphics are simply made, But the music which although fine is a bit too loud for me 🙉. I like many others have a learning difficulty where concentration is difficult, so I had a problem with trying to listen to the talking without the music seeming to take over a bit .😵 So I'm not sure if I can watch any of your other videos, never mind I'm sure I'll find something for me.😀 Great work though. 👍

  • XxItsMagicalxX
    XxItsMagicalxX  6 hours back

    Memory cells= Vietnam veterans

    • Снежный Джони

      so you be sayin that while i wank some organism are dying just to keep me alive?

      • Queen Travels
        Queen Travels  8 hours back

        So it's correct to say "I'm dying inside" because of this loads of cell deaths happening in my body.

        I have had many suicides that I know nothing about. 🤔

        • Astrono 1
          Astrono 1  10 hours back

          5 YEARS AGO?!?!

          Im old

          • how-to-HALLIE
            how-to-HALLIE  17 hours back

            Bacteria: Yayy free space!
            Immune system: *I'mma bout to end this man's whole career*

            • Abbi Quigley
              Abbi Quigley  20 hours back

              Ok this is amazing

              • Field Marshal Akajima
                Field Marshal Akajima  22 hours back

                The military inside your body

                • Alexander Mcharek
                  Alexander Mcharek  1 days back

                  Me: gets a cold
                  Immune system: *Hell March starts playing*

                  • GillRoy Mac
                    GillRoy Mac  1 days back

                    "I pity the fool who enters this body uninvited!"
                    - Mr T-cell

                    • Unknown person
                      Unknown person  2 days back

                      I am proud to say that I'm not alone I have friends fighting for me!!!

                      • Black Pineapple
                        Black Pineapple  2 days back

                        Little red ball:
                        IM FUCKING READY!!!

                        • Caidyn Zoie
                          Caidyn Zoie  2 days back

                          I have a cold and I am watching this :I

                          • HazzyGamer
                            HazzyGamer  2 days back

                            ı only understand from this vid umminate system agar io :D

                            • Anonymous
                              Anonymous  2 days back

                              Gets a small paper cut

                              Immune system: *Remember, no bacterias*

                              • DeusEx Machina
                                DeusEx Machina  2 days back

                                To me, as a physicist doing research in neuroscience, this was very helpful!
                                Interdisciplinary scientists often struggle to get a grip on the numerous concepts, relevant to their research. I would love to watch such well explained, visualized and simplified videos on more subjects.
                                A personal item on the wish list would be microglia and the blood-brain barrier.

                                • Bryton
                                  Bryton  2 days back


                                  Me: *gets cut*

                                  Immune system: this is a avenger level threat

                                  • Hollow Beat
                                    Hollow Beat  2 days back

                                    Immune system in war after 5 days: tis the time for kamikaze

                                    • Scuba
                                      Scuba  2 days back

                                      Ummmm... Tetanus?

                                      • Blazeee
                                        Blazeee  2 days back

                                        this video was supposed to be new

                                        • Roblox Cat
                                          Roblox Cat  2 days back

                                          I'm sick rn.
                                          This made me understand why I'm so god damn tierd❤️

                                          • Nassi Love
                                            Nassi Love  3 days back

                                            "Your skin" defense is really bad. I might need to catch a new Pokemon... Like come on! The rusty nail is lvl 4! You're lvl 28! So much grinding for nothing...

                                            • Arun Rabe0505
                                              Arun Rabe0505  3 days back

                                              The thought between the immune system and our system of life is so good 😍

                                              • Bear Grylls
                                                Bear Grylls  3 days back

                                                Did I tell you about the immune system?

                                                • MINECRAFT IS DA BEST
                                                  MINECRAFT IS DA BEST  3 days back

                                                  SO YOUR SAYING FOR 0291910919192019191991877081718P7807P878017P8778USQQ,O1UWWY12I7727Q6Q6717166171828828181717728282717.19289182982992 SECOND OF MY LIFE I'VE BEEN ATACTED

                                                  • KiNgoFtHeGoDs434
                                                    KiNgoFtHeGoDs434  3 days back

                                                    With a bare cut, your body is like *”Peace was never a option”*

                                                    • cartucho da internet
                                                      cartucho da internet  3 days back


                                                      • BIG Wheat fan
                                                        BIG Wheat fan  3 days back

                                                        When the German start speaking bullshit english

                                                        • Smart Burrito
                                                          Smart Burrito  3 days back

                                                          The human body is smarter than the actual human.

                                                          • oscar sagot
                                                            oscar sagot  3 days back

                                                            Isn't it the mast cell that send a protein signal to the blood vessel first, then the monocytes and granulocytes become macrophages after they leave the blood cell ?

                                                            • Sara Alheidous
                                                              Sara Alheidous  4 days back

                                                              wonderful interesting video, please we want more of these medical videos and in more details

                                                              • Hello im random Lol
                                                                Hello im random Lol  4 days back

                                                                Cut on finger: exists
                                                                Meanwhile in the cut: SEND ALL OF OUR T AND B CELLS THERES TOO MANY BACTERIA IN THE WOUND

                                                                • Pranjali Patankar
                                                                  Pranjali Patankar  4 days back

                                                                  This video made me want to eat healthy in order to repay my immune cells😊

                                                                  • Aisha Curiouss
                                                                    Aisha Curiouss  4 days back

                                                                    You should name the video "IMMUNITY WAR"

                                                                    • Scruffy ,
                                                                      Scruffy ,  4 days back

                                                                      When I get a cut uhh nothing

                                                                      Immune system peace was never an option

                                                                      • Enviable
                                                                        Enviable  4 days back

                                                                        Anyone else notice at 6:30 they spelled doctors wrong

                                                                        • Carol
                                                                          Carol  4 days back

                                                                          i heard “billions of bacteria, fungi (...) are trying to make you their hoe”
                                                                          and tbh i’m not mad

                                                                          • KalzombiePlays
                                                                            KalzombiePlays  4 days back

                                                                            Me: Gets a Papercut

                                                                            Also me: I’m fine

                                                                            Bad bacteria: OMAERU WA MOU SHINDERU

                                                                            Immune System: NANI?!

                                                                            • Julius Cooper
                                                                              Julius Cooper  5 days back

                                                                              we are in the endgame now
                                                                              me fi

                                                                              • Austinb Great job bright side

                                                                                bactire fuck you immune system

                                                                                • The Most Original Gamer

                                                                                  The comment section is filled with:-

                                                                                  10℅ funny jokes
                                                                                  90% copypasta

                                                                                  • tina verdon
                                                                                    tina verdon  5 days back


                                                                                    • qwerty is my name
                                                                                      qwerty is my name  5 days back

                                                                                      0:00 Is that a Poké Ball on her belt?

                                                                                      • Jordans Gaming Show
                                                                                        Jordans Gaming Show  5 days back

                                                                                        Didn’t know every time I get a cut there’s a war in my Body

                                                                                        • Jeremy Cheng
                                                                                          Jeremy Cheng  5 days back

                                                                                          Iz cool

                                                                                          • Balkis Ayachii
                                                                                            Balkis Ayachii  6 days back

                                                                                            want to ace that biology quiz about the immune system? Watch this video and Cells at Work anime

                                                                                            • 임준서
                                                                                              임준서  6 days back

                                                                                              시작부터 이시국

                                                                                              • Mico Lim
                                                                                                Mico Lim  6 days back

                                                                                                A cut is a portal. *To the Endgame Battlefield!* the bacteria say.