Ch4 L3 Introduction to Invertebrates

Echinoderms are different from most other invertebrates because they have an

• endoskeleton

• exoskeleton

All worms have _________________ symmetry.

• Bilateral

• radial

Which of the following is not a group of invertebrates?

• sponges

• mollusks

• fishes

• cnidarians

The simplest animals with a brain are ______________ worms.

• segmented

• round

• flat

________________ have stinging cells and take food into a central body cavity.

• sponges

• echinoderms

• arthropods

• cnidarians

To which group of invertebrates do cephalopods, such as squid, belong?

• arthropods

• cnidarians

• mollusks

• echinoderms

About __________________ of all know animals are invertebrates.

• 4 percent

• 50 percent

• 90 percent

• 96 percent

An echinoderm is an invertebrates that has a _________________.

• radial

• bilateral

________________ invertebrates that have hard outer covering and segmented bodies.

• sponges

• arthropods

• cnidarians

• mollusks

Mollusks with two shells are called _____________.

• cephalopods

• sea star

• bivalves

• gastropods