Chapter 26, Problem 7A

Summary Introduction

Introduction :

The arthropods are divided into groups according to the body segment, mouthparts, and appendages of their body. The groups include crustaceans, spiders and their relatives, and insect and their relatives. The crustaceans have two pairs of antennae, mandibles, two compound eyes, five pairs of legs, and they are swimmers. The spiders and their relatives do not have antennae, six pairs of legs, and two body sections. The insects and their relatives have antennae, three pairs of legs, and three body areas.

Answer to Problem 7A

Correct answer :

The correct answer is option (C) motion.

Explanation of Solution

Explanation/justification for the correct answer :

Option (C)motion.The function of exoskeleton is to support the internal body of the arthropodsincluding the muscle movement and it depends on the size of the muscle and the exoskeleton thickness. So, the correct answer is option (C).

Explanation for incorrect answer :

Option (A)diet. The size of muscle and the exoskeleton thickness is interrelated, if the muscle size is short it affects the motion of the organism not the diet. So, this is an incorrect option.

Option (B) habitat. The arthropods are found in almost all habitats. And the habitat is not related to the muscle size. So, this is an incorrect answer.

Option (D) size. The function of exoskeleton is to support the internal body of the arthropods including the muscle movement. Therefore, the relationship between the muscle size and the exoskeleton thickness limits its motion not size.So, this is an incorrect answer.