Science: Invertebrates: Insects, Arachnids, and Mollusks

An animal has six legs, three body parts, and two antennae. Is it an insect, an arachnid, or a mollusk? Explain how you know.

A spider has eight legs and no antennae. Is a spider an insect, an arachnid, or a mollusk? Explain your answer.

A snail has a soft body and often carries a shell. Is it an insect, an arachnid, or a mollusk? Explain how you know.

Name one way insects are different from arachnids.

A crab is not one of the three groups in this worksheet. Explain why a crab is not an insect, arachnid, or mollusk.

A bee, an ant, and a butterfly all belong to the same group. What group is it, and what trait do they share?

Why is an octopus classified as a mollusk even though it does not have a shell?

Which group usually has antennae: insects, arachnids, or mollusks? Write a sentence to explain.

A scorpion has eight legs and belongs to the same group as spiders. What group is it in, and what feature helps you classify it?

Explain why a clam is a mollusk.

A student says a centipede is an insect because it has many legs. Is the student correct? Explain your answer.

Write one sentence that tells how insects, arachnids, and mollusks are alike.