Whether you caught the common cold or came down with something much worse, have you ever wondered what is actually going on inside your body? Click here to see more videos: http://www.m301.me/lifenoggin Life Noggin is a weekly animated educational series. Whether it's science, pop culture, history or art, we explore it all and have a ton of fun doing it. Follow Us! https://twitter.com/LifeNoggin https://facebook.com/LifeNoggin https://www.LifeNoggin Life Noggin Team: Animation & Designed by: http://www.krofl.com Voiced by: http://youtube.com/patdoesit Written by: https://www.youtube.com/AwkwardAdoles... Produced by: http://www.twitter.com/IanDokie Sources: http://health.howstuffworks.com/human-body/systems/immune/immune-system.htm http://www.mayoclinic.org/diseases-conditions/fever/basics/causes/con-20019229