Hank tells us about the team of deadly ninja assassins that is tasked with protecting our bodies from all the bad guys that want to kill us - also known as our immune system. Like CrashCourse - www.facebook.com/YouTubeCrashCourse Follow CrashCourse - www.twitter.com/TheCrashCourse Table of Contents 1) Innate Immune System 1:45 a) Mucous Membranes 2:54 b) Inflammatory Response 3:44 c) Leukocytes 4:45 2) Open Letter 6:33 a) Natural Killer Cells 6:56 b) Dendritic Cells 7:57 3) Acquired Immune System 8:36 a) Antibodies 9:08 b) Lymphocytes 9:48 c) Cell-Mediated Response 10:17 d) Humoral Response 13:00 References Campbell Biology, 9th ed. faculty.stcc.edu/AandP/AP/AP2pages/Units18to20/blood/white.htm highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter24/animation__the_immune_response.html This video uses the following sounds from Freesound.org: "Pigs-01.flac" by Erdie "straw slurp.wav" by dparke4 "Disgusting Slop.wav" by Ighuaran "Sonar Ping.wav" by digifishmusic "Swishes.wav" by Pogotron "swing.mp3" by morgantj crash course, crashcourse, biology, immune system, anatomy, physiology, human, health, microscopic, pus, pathogen, bacteria, body, organism, virus, immunity, innate, acquired, animal, vertebrate, germ, skin, mucous membrane, digestive tract, mucus, inflammatory response, mast cells, histamine, allergic, allergy, infection, phagocyte, macrophage, natural killer cell, lymphocytes, white blood cells, antigen, t cell, humoral response Support CrashCourse on Subbable: subbable.com/crashcourse