How would you classify this organism? Compare the characteristic structures of invertebrate animals (including sponges, segmented worms, echinoderms, mollusks, and arthropods) and vertebrate animals (fish, amphibians, reptiles, birds, and mammals) Classify organisms, objects, and materials according to their physical characteristics by using a dichotomous key Why do scientist Classify? Link: Is the animal we observed a skate- ray- shark? Research Question: How are sharks and rays categorized?

How do these pictures compare and Differ?

Dichotomous key Students will download the Dichotomous key on i- pads. Read and complete the dichotomous key in groups. See attachment. Share with group Have you changed your mind? Is this organism a shark, ray, or skate?

With your group begin classifying the organisms on the Dichotomous key. After completion have two groups get together and discuss their answers. If you disagree decide why? Ocean Organisms Dichotmous key?