Insect Metamorphosis - Ch. 16

A challenge to Evolution

Hormones in the Molting Process

Brain Hormone (Prothoracicotropic), Ecdysone, Juvenile, Bursicon

Brain Hormone Function

initiates molting

Ecdysone Function

activates the epidermal cells to produce a new exoskeleton and molting fluid

Juvenile Hormones Function

interact w/ ecdysone to determine which stage of metamorphosis the insect should be in

Bursicon Function

triggers the sclerotization of the exoskeleton (soft and light in color)

Imaginal Discs define

undifferentiated cells that are set aside during embryonic development and carried through the larval stages

Pupal exoskeleton

most of the insides of the caterpillar are broken down except for a few nerves and muscles

nectar siphoning mouthparts

Leaf Chewing mouthparts are replaced by

compound eyes

Simple eyes are replaced by

no wings

four wings covered with scales will replace with

new respiratory system

that can sustain flight must be created

digesting nectar

digestive system changes from digesting plant food