Chapter 26.1, Problem 6MI

Summary Introduction

To identify:

The structures attached to or contained in the main body regions of arthropods

Introduction:

Arthropods have segmented bodies and tough exoskeletons with jointed appendages. About 70 to 85 percent of all named animals are arthropods. Majority of species belonging to this phylum are insects which include moths, beetles, butterflies, bees and wasps.

Answer to Problem 6MI

  

Explanation of Solution

The segmented body of an arthropod is divided into three regions; head, thorax and abdomen. Head forms the anterior part, thorax forms the middle part and abdomen forms the posterior part of an arthropod’s body.

The heads of arthropods have mouthparts for feeding and different types of eyes. Many also have antennae. Antennae have sensory structures that contain receptors for sense of smell and touch. The thorax is the middle part of the body which consists of three fused main segments to which legs and wings are attached.

The abdomen which also contains fused segments and lies in the posterior part of the animal bears additional legs and contains digestive structures and reproductive structures.

In some arthropods the thorax region is fused with the head into a structure called a cephalothorax.