You find a wormlike animal while scuba diving and want to determine whether it is a nudibranch, a polychaete, or a flatworm. Finding which of the following traits would best help you classify the mystery animal?

Question

Quizplus · Accepted Answer

Bristle-like structures on tiny appendages are a characteristic of polychaetes. Nudibranchs and flatworms do not have bristle-like structures.

Answer: B 
 A coelom (a fluid-filled body cavity) is a characteristic of polychaetes and nudibranchs. Flatworms do not have a coelom.

Answer: C 
 The ability to swim is a characteristic of polychaetes. Nudibranchs and flatworms do not have this ability.

Answer: D 
 Bright coloration is a characteristic of nudibranchs. Polychaetes and flatworms may also have bright coloration, but it is not as diagnostic as it is in nudibranchs.

Answer: E 
 Sexual reproduction is a characteristic of all three groups (polychaetes, nudibranchs, and flatworms) and is not diagnostic.

You Find a Wormlike Animal While Scuba Diving and Want