This week's slice of scientific YouTube comes from the excellent Ted-Ed website. There is an excellent lesson supporting the video, which explores how nerve cells function in the human body, comprising a short quiz, a more challenging "thinking" activity and loads of supporting resources. Of course, Ted-Ed allows you "flip" the video to create your own lesson, if you feel the questions or activities don't suit your own students. According to the Ted-Ed website, this lesson reveals that "at any moment, there is an electrical storm coursing through your body. Discover how chemical reactions create an electric current that drives our responses to everything from hot pans to a mother’s caress". Click here to visit the lesson on Ted-Ed now (but maybe watch the video first).