It might, for instance, also describe differences in flower anatomy and leaf shape. Unless you've had botany classes or already taught yourself a lot, of course not. And the first time any aspiring naturalist decides to tackle keys, it's the same way with them. Happily, however, there's a way to not only dominate these formidable terms and concepts, but also to absolutely relish running into them. Here's a definition in which you know all the terms.
Fertilization is sex at the genetic level, and seed are seed.
Naturally there are shortcuts where you can avoid too much leapfrogging. For example, one day a key led me to discover the amazing apparatus at the right, which I drew using a microscope. This is a kind of comb found on a leg of a Fire Ant. When I was discovering all this, thanks to a key drawing my attention to it, I found that my mind was refreshed with forms, textures, relationships, and processes. In fact, some would say that keying out plants and animals is nothing less than a form of meditation.