I've always had qualms about pple using the index to look up something in a textbook. When a pass leader recommends doing that to look for definition of terms, when I see my fellow classmates looking through the index etc, i just feel in my heart and brain that something is not right. As if some procedural step has been jumbled or someone is cheating. Fair, its a fricking 600 page textbook, an index would be like a crtl f- god sent to those unresponsive, unscrollable deadpan pages. But but- You are a student! And you are learning. Surely the content page, which contains the main concepts would be more useful to you than an alphabetical list? Surely locating a term using your existing knowledge of it, through the various body systems nicely segmented out for you in the content page, is more satisfying than trawling through an alphabetical list where neighbours are as related as a STOmach ulcer to a STOp codon??