BIOL 317 Lecture Notes - Lecture 5: Arthropod Cuticle, Pupa, Sclerotin
Document Summary
The integument, molting and endocrine control: morphology and chemistry of the insect integument, sclerotization of insect cuticle, physical aspects of molting, endocrine control of molting and development. Apolysis separation of the epidermis from the cuticle of the previous stage: ecdysis casting off (or escape from) the residual cuticle of the previous stage. A fully formed insect inside the old cuticle prior to ecdysis is called a pharate. The cast cuticle is called an exuvium: sclerotization chemical process that hardens the outer section of cuticle. Until sclerotization is complete after the final molt, the insect is referred to as a teneral adult. In many insects, ecdysis depends on blood pressure and/or air pressure; e. g. prolonged contraction of the abdomen forces blood into the head/thorax. Nb if the foregut of a cockroach nymph is punctured, it cannot molt. Ecdysis is often aided by gravity the insect hangs upside down, secured by the claws of the hind tarsi.
