In exoskeleton of arthropods

I. chitinous plates present over the body are called sclerites

II. sclerites are joined with the help of soft membranous structures called arthrodial membrane

III. the dorsal sclerites are called tergum, ventral sclerites as sternum and lateral sclerites are called pleura

IV. epidermis is present above the cuticle, called hypodermis

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