Immune System, Part 2: Crash Course Anatomy & Physiology #46

In the penultimate episode of Crash Course Anatomy & Physiology, Hank explains your adaptive immune system. The adaptive immune system's humoral response guards extracellular terrain against pathogens. Hank also explains B cells, antibodies, and how vaccines work. 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: https://apple.co/3d4eyZo Download it here for Android Devices: https://bit.ly/2SrDulJ Chapters: Introduction: Adaptive Immune Responses 00:00 How B Cells Identify Antigens 2:14 B Cells Become Effector Cells & Memory Cells 4:05 How Antibodies Fight Antigens 5:22 Active and Passive Humoral Immunity 6:03 How Vaccines Work 6:27 Review 8:30 *** Crash Course is on Patreon! You can support us directly by signing up at   / crashcourse   Thanks to the following Patrons for their generous monthly contributions that help keep Crash Course free for everyone forever: Mark, Eric Kitchen, Jessica Wode, Jeffrey Thompson, Steve Marshall, Moritz Schmidt, Robert Kunz, Tim Curwick, Jason A Saslow, SR Foxley, Elliot Beter, Jacob Ash, Christian, Jan Schmid, Jirat, Christy Huddleston, Daniel Baulig, Chris Peters, Anna-Ester Volozh, Ian Dundore, Caleb Weeks -- Want to find Crash Course elsewhere on the internet? Facebook -   / youtubecrashcourse   Twitter -   / thecrashcourse   Tumblr -   / thecrashcourse   Support Crash Course on Patreon:   / crashcourse   CC Kids:    / crashcoursekids