ZOO 2700 Lecture 24: Lecture 24

• School: University of Guelph
• Department: Zoology
• Course: ZOO 2700
• Professor: Alex Smith

Document Summary

Legs usually attached to thorax section: 3 pairs. Trachael system: transfers air to deeper parts of the body as the muscle used for walking and flying. Entognatha: wingless, mouth parts sunk in head, ametabolous: don"t have metamorphosis; direct developers. Ectognatha: insects in the narrow sense, mouth parts protrude, compound eyes/ocelli. Neoptera: flex their wings, not dragonflies, mayflies, etc. Upstroke: dominated by depression of tergite- vertical muscles. Ametabolous: young identical to adults, collembula, protura. Juveniles have no wings: don"t resemble adults a whole lot, mayflies, dragonflies, etc. Juveniles have no wings but do resemble adults: grass hoppers. Ecdysteroids: steroid hormones derived from ecdysis: independently evolved. Immaginal discs: small pockets that are contained in the larva, neural cells that give rise to the wings. Can distinguish the head from the thorax and abdomen. Earlier pesticides used were juvenile hormones, the insects would come into contact with these and would never become pupa, so would become so big and die.