Chapter 26, Problem 26A

Summary Introduction

To write:

The term that does not belong in the group.

Introduction :

Arthropods have complex organ systems that allow them to live in a variety of habitats. Adaptations to several organ systems, like the respiratory system and the nervous system, have contributed to the development of these animals. Insects make up the largest group of arthropods. They have three body segments and six legs. Grashoppers, bettles, butterflies, and lice are some members of class insecta.

Explanation of Solution

As insects develop, they undergo a series of changes in their body structure. This series of changes is known as metamorphosis. Insects that undergo metamorphosis usually undergo four stages on their way to adulthood: egg, larva, pupa and adult. The insects begin their lives as a fertilized egg, and they hatch into a larva.The larva is the insect's free-living wormlike stage. The pupa stage is a period of reorganization during which larva tissues and organs are broken down and replaced with adult tissues. After that the adult insect emerges from the pupa.

Nymph is one of the stages of incomplete metamorphosis. In this case, only three stages of development are involved- egg, nymph and adult. A nymph hatches from the egg and has the same general features as the adult but is smaller and may lack certain appendages and lack the ability to reproduce.

Castes are classes within a group of insects. The caste members have marked physiological differences within the species from those of other castes. For example, bees have castes such as workers, drones and queens, whose members are specially adapted to perform their particular role within the colony.

Thus, the term caste does not fit with the group as it is not a stage of development or growth in insects.

Conclusion

The term caste does not fit in with the group as it is a division within an insect group that performs specific functions for their survival.