Extension of body (ex: arm, leg, antennae)
Body cavity with fluid
Cephal - Head (sensory)
Thorax - Chest (movement) (wings & legs)
Abdomen (reproduction / digestive)
Chitin protects internal organs, but does not grow with animal
Animal has to “molt“, or shed skin, and form a new exoskeleton
Period in which animal molts, afterwards are very vulnerable
Incomplete 3 stages (Egg → Nymph → Adult)
Complete 4 stages (Egg → Larva → Pupa → Adult)