Question

what is chitin plate in a cockroach called

Answer 1

The chitin plates in Cockroaches which Constitutes the exoskeleton of this arthropod are called 'Sclerites'.
These chitin plates occur in each segment.
Sclerites of dorsal side are called Tergum or Tergite.
Sclerites of Ventral side are called Sternum or Sternite and Sclerites of Lateral side are called Pleurons or pleurites.

These sclerites join each other by a membrane called Articular membrane.

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