Chapter 25, Problem 23A

Summary Introduction

Introduction:

The Mollusca is a phylum of animal kingdom. They are mostly marine, which makes up the second most diverse phylum of the animals. They have soft body and their dorsal epidermis is modified to form a mantle. Bivalves are a type of mollusks.

Answer to Problem 23A

Correct answer:

Option (A).

Explanation of Solution

Explanation/justification for the correct answer:

Option (A) maintain its shell. The shell of the bivalve is modified from the mantle. In a case, when the bivalve is damages the mantle, shell will be damaged. Hence, the correct answer is option (A).

Explanation for incorrect answer:

Option (B) digest. The mantle is not involved in the digestion process. Hence, it is an incorrect answer.

Option (C) circulate blood. The mantle is not involved in circulation of blood. Hence, it is an incorrect answer.

Option (D) excrete waste. The damage to the mantle does not affect the excretion in the bivalves. Hence, it is an incorrect answer.