Regular Biology Chapter 28 Waggy The Insects Regular Biology Chapter 28 Waggy

Chapter Objectives 1. Discuss & list the general characteristics of insects 2. Trace the taxonomy of the Class Insecta 3. Discuss the characteristics of the external structure of the grasshopper 4. Follow the digestive system of the grasshopper

Chapter Objectives… 5. Understand the way the circulatory system of the grasshopper works 6. Discuss the nervous system of the grasshopper 7. Compare & contrast complete metamorphosis & incomplete metamorphosis

Insect features The study of insects is called entomology Exoskeleton is made up of chitin Bodies are in three segments: 1. Head Mandible (movable jaws) antennae 2. Thorax Three pairs of jointed legs Up to two pairs of wings (if any) 3. Abdomen Composed of up to 11 segments

Insect Features Insects have thrived for more than 400 million years Insects live everywhere on earth except saltwater

Insect Features Adaptations that have allowed insects to become so successful on Earth are: 1. Flight 2. Small size to evade predators & inhabit tiny habitats 3. Short life spans & tons of eggs allow for Natural selection to work faster in insects Today, insects account for more than half of all animals species on Earth

Taxonomy Domain: Eukarya Kingdom: Animalia Phylum: Arthropoda Class: Insecta Order: there are nine: 5. Orthoptera 6. Coleoptera 7. Diptera 8. Hymenoptera 9. Lepidoptera 1. Hemiptera 2. Homoptera 3. Isoptera 4. Odonata

2. Order: Homoptera 1. Order: Hemiptera ‘half wing’ 55,000 different species These are the true bugs Damage crops, garden plants & transmit disease 2. Order: Homoptera ‘like wing’ 22,000 different species Aphids, mealybugs, cicadas

3. Order: Isoptera 4. Order: Odonata ‘same wing’ 2,000 different species Termites 4. Order: Odonata ‘toothed wing’ 5,000 different species Dragonflies & damselflies

5. Order: Orthoptera 6. Order: Coleoptera ‘straight wing’ 30,000 different species Grasshoppers, crickets, katydids 6. Order: Coleoptera ‘sheathed wing’ 400,000 different species Weevils, ladybugs, all beetles

7. Order: Diptera 8. Order: Hymenoptera ‘two wing’ 120,000 different species Mosquitoes, flies & gnats 8. Order: Hymenoptera ‘membrane wing’ 100,000 different species Bees, wasps, ants

9. Order: Lepidoptera ‘scaled wing’ 140,000 different species Butterflies & moths

The Grasshopper: external structure The head: Simple & compound eyes Unbranched antennae Mouthparts

The Grasshopper: external structure… The thorax is divided into three parts: Prothorax Attaches to the head & has the first pair of walking legs Mesothorax Has the forewings & the second pair of walking legs Metathorax Attaches to the abdomen and has the hindwings and the large jumping legs

The Grasshopper: external structure… Abdomen: The segments are made up of upper and lower plates of exoskeleton joined by a tough but flexible sheet of exoskeleton The entire grasshopper is covered by a waxy cuticle to slow water loss