SME
Grade 9 Science · Problem type
A dichotomous key
Use this for “Use the key to name the animal: it has no backbone and a segmented body.”
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Every animal starts at the top: a backbone or not splits the six into two groups.
Assumptions
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A dichotomous key asks one yes-or-no question at a time about a trait you can see.
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Each answer leads to the next question or to a name, so every path ends at one organism.
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