Book excerpt: Take a tour of one of the most complex, diverse and downright unusual places on the entire planet - the human body! Find out all about what makes YOU tick, from the wonders of the human brain to the tingling in your ticklish toes. From crazy bodily functions to bizarre real-life medical cases, this is the ultimate guide to getting to know yourself, inside and out! Operation Ouch! is a BAFTA-winning CBBC series, from the makers of Embarrassing Bodies and 10 Years Younger. It's presented by real-life doctors (and twin brothers) Chris and Xand van Tulleken.