Question

Features common in silver fish, scorpion, dragonfly and prawn are
A) Three pairs of legs and segmented body
B) Chitinous cuticle and two pairs of antennae
C) Jointed appendages and chitinous exoskeleton
D) Cephalothorax and tracheae

Answer 1

Hint:To make the study easier the organisms are classified on different basis, one such way is to characterise organisms on the basis of their body plan. The basic body plan includes classification on the basis of level of organisation, body symmetry, body cavity and much more.

Complete answer:
First the organisms are classified on the basis of level of organisation means cellular level is exhibited by poriferans, tissue level is exhibited by coelenterates and ctenophore, organ level is exhibited by Platyhelminthes and aschelminthes and organ system is exhibited by Annelida to hemichordate. Silverfish, scorpion, dragonfly and prawn are animals that belong to arthropods.

Now let us gather information about given options :-
A) Three pairs of legs and segmented body : Most arthropods have three pairs of legs but some of them also possess four pairs of legs such as Arachnids.
B) Chitinous cuticle and two pairs of antennae : Mollusca are characterized by having soft bodies and possessing antennae. They are usually found in all habitats . Cuttle fish and devil fish belongs to this
C) Jointed appendages and chitinous exoskeleton : Arthropod is the largest phylum of animal kingdom with about 9,00,000 species and has jointed appendages. Their exoskeleton is made up of chitin which prevents them from desiccation. This phylum is a much heterogeneous group including a variety of animals differing in structure, habitat, feeding habits and other characteristics. All three of them are present in this
D) Cephalothorax and tracheae : cephalothorax are present only in some like arachnids and in arachnids only spiders.

Hence the correct answer is option ‘C’ i.e, Jointed appendages and chitinous exoskeleton.

Note:The body of arthropods is covered by a hard, water-proof exoskeleton made up of chitin. This chitinous exoskeleton is one of the reasons for the successful existence of arthropods on the earth. It provides protection and support to the body and the internal organs present inside the body. Moreover, it also prevents the loss of water due to evaporation thus enabling the arthropods to live in relatively dry environments.