Chapter 25, Problem 33A

Summary Introduction

Introduction :

The invertebrates are the organism that lack vertebral column and are comparatively less complicated. The Annelida a phylum that belong to segmented worms. The polychaetae are the organism that have multiple segmented body. They are generally marine and have parapodia for movement.

Answer to Problem 33A

Correct answer :

Option (B).

Explanation of Solution

Explanation/justification for the correct answer :

Option (B) Parapodia. The characteristics feature of the polychaeta is presence of multiple setae and parapodia from the body segments. Hence, the correct answer is option (C).

Explanation for incorrect answer :

Option (A)Foot. Mollusks have foot, polychaeta do not have complete foot. Hence, it is an incorrect answer.

Option (C) sucker. The sucker is a characteristic of tapeworms and leech. Hence, it is an incorrect answer.

Option (D) shell. The shell is generally present in mollusks, annelids do not have it. Hence, it is an incorrect answer.