USING A DICHOTOMOUS KEY
FIGURE 18–2 A dichotomous key is used to identify organisms. It consists of a series of paired statements or questions that describe alternative possible characteristics of an organism. The paired statements usually describe the presence or absence of certain visible characteristics or structures. Each set of choices is arranged so that each step produces a smaller subset. Suppose you found a leaf that you wanted to identify. The leaf looks like the one shown here. Use the key to identify this leaf.
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