InsectsChapter 10 Section 3

Body Structure

Arthropods with three body sections, six legs, one pair of antennae, and usually one or two pairs of wings

Three body sections are the head, thorax, and abdomen

Body Sections: Head

Insect’s sense organs found in head (eyes/antennae)

Two large compound eyes◦Compound eyes contain many lenses, keen at seeing movement

Body Structure: Thorax

Insect’s midsectionWhere wings and legs are attached

Only invertebrates that can flyCan travel long distances to find

mates, food, and new places to live

Body Structure:Abdomen

Internal organs found in the abdomen

Small holes outside of abdomen allow air, which contains oxygen, to enter the body through tubes

Obtaining Food

“If it is living, or if it once was living, some kind of insect will eat it.”

Mouthparts are adapted for a highly specific way of getting food

Life Cycle

Begin life as tiny, hard-shelled, fertilized eggs

Either go through… ◦Complete metamorphosis◦Gradual metamorphosis

Complete Metamorphosis

4 different stages: egg, larva, pupa, adult

Insect begins life as a tiny, hard-shelled fertilized egg

The eggs hatch into larvae (usually look like worms)

Larva will then enter next stage and become a pupa, insect is enclosed in a protective covering◦Pupa does not eat/barely moves, but it is NOT

restingWhen development is complete, adult

leaves pupal case

Gradual Metamorphosis

No distinct larval stage

Egg hatches into a stage called a nymph◦Nymph: usually looks like the adult insect without wings

Nymph may molt several times before becoming an adult

Grasshoppers, termites, cockroaches, dragonflies

Video Clips

https://vimeo.com/37289745

https://vimeo.com/album/3277606/video/37321126