An Introduction to Invertebrates

A set of flashcards covering the key concepts related to invertebrates, their classification, characteristics, and significance.

What is the significance of classifying invertebrate species into groups based on evolutionary relationships?

It helps us understand their great diversity.

What percentage of known animal species do invertebrates account for?

Over 95%.

What are the two body forms in Cnidaria?

The sessile polyp and motile medusa.

How do sponges (Porifera) capture particles suspended in water?

By filtering water through their porous bodies.

What unique characteristic do echinoderms have in terms of symmetry?

They are bilaterally symmetrical as larvae but not as adults.

What are nematodes commonly known as?

Roundworms.

What is the structure that Cnidarians use to capture prey?

Tentacles armed with cnidocytes.

How do arthropods differ from other invertebrates?

They possess a segmented body, hard exoskeleton, and jointed appendages.

What type of circulatory system do cephalopods have?

A closed circulatory system.

What are the two forms in which brachiopods can be found?

Attached to the seafloor or free-swimming.