* 07/16/96 ARTHROPODS BIOLOGY MR. Quinn … 2/25/2019 *

Animals of Phylum Arthropoda * 07/16/96 Animals of Phylum Arthropoda Termites, ticks, scorpions, grasshoppers, flies, mosquitoes, lobsters, crabs, bugs,spiders, centipedes, millipedes, daphnia,crayfish,beetles,dragon flies, bees, wasps, daddy-long legs, mites, fleas, trilobites, butterflies, moths, barnacles, ants,……..and many many more!!!!! 1 2/25/2019 *

Characteristics of Arthropods !! * 07/16/96 Characteristics of Arthropods !! Invertebrates with an exoskeleton! Jointed appendages (legs) Bilaterally symmetrical Has a true coelom Segmented body 2 2/25/2019 *

What are the advantages or disadvantages of an exoskeleton?? * 07/16/96 What are the advantages or disadvantages of an exoskeleton?? Protection -made of chitin and protein- hard and thick !! Supports internal organs Provides for muscle attachment Heavy-disadvantage Can’t grow, so it must be shed by molting periodically! 3 2/25/2019 *

* Segmentation 07/16/96 Most arthropods have three body segments! HEAD, THORAX, and ABDOMEN Sometimes the head and thorax are fused together to form a CEPHALOTHORAX- like in lobsters! All legs and wings attach to the thorax! 4 2/25/2019 *

How do Arthropods breathe?? * How do Arthropods breathe?? 07/16/96 Some land Arthropods breathe through tiny openings on their body called spiracles which lead to tubes within the body called tracheal tubes! - crickets! Other land arthropods (spiders) breathe using book lungs found just behind the legs on the body! Aquatic arthropods have gills!! 5 2/25/2019 *

Senses found in Arthropods!- from a brain and ventral nerve chord!!! * Senses found in Arthropods!- from a brain and ventral nerve chord!!! 07/16/96 Antennae are sensitive to movement, sound and chemicals! Antennae also are used to communicate between arthropods! Pheromones are chemical-odor signals given off by arthropods! EYES - both simple and compound! Simple eyes detect light/dark! Compound eyes have many lenses together forming an image! Excellent for detecting movement! 6 2/25/2019 *

Sight through a Bees Compound Eye * 07/16/96 Sight through a Bees Compound Eye Bee Sight Human Sight 2/25/2019 *

Circulation and Digestion in Arthropods! * Circulation and Digestion in Arthropods! 07/16/96 Open circulatory system- blood flows into spaces in the body- not kept in blood vessels! Dorsal heart ! Complete digestive system-mouth-crop-stomach-intestines-anus! Digestive enzymes breakdown food! Chewing mandibles , or sucking mouth parts are strong! Malphigian Tubules filter wastes into the intestines! 7 2/25/2019 *

Reproduction in Arthropods ! * 07/16/96 Reproduction in Arthropods ! Most arthropods have separate sexes (males/females) Internal Fertilization- eggs protected inside female. A few are hermaphrodites Some show parthenogenesis- young forming from unfertilized eggs! 2/25/2019 *

Arthropods and Humans ?? The Good, the Bad and the Ugly!!! * 07/16/96 Arthropods and Humans ?? The Good, the Bad and the Ugly!!! Great pollinators …bees, wasps! Provide honey, shellac, wax and silk! Alternative to pesticides - lady bugs, praying mantis Used in genetic research to make artificial skin, surgical sutures, and anti-fungal medicine from crab shells! Problems: eating our food! Spread diseases- malaria, yellow fever! 2/25/2019 *

Diversity - The Arachnids!!- spiders, scorpions, mites, and ticks! * Diversity - The Arachnids!!- spiders, scorpions, mites, and ticks! 07/16/96 30,000 species of spiders - but only about a dozen are poisonous to humans! 2 body parts - cephalothorax and abdomen! 6 pairs of appendages- 2 Chelicera-fangs, two pedipalps for handling food and used in reproduction, and 8 legs!! 2-6 silk glands in the abdomen-passing the liquid silk to the spinnerets which knit it into thread! No mandibles - but a sucking stomach! No antennae, and only simples eyes -usually 8 Ticks and mites have only one body part!! (All fused) 2/25/2019 *

* 07/16/96 Arachnids Chelicera 2/25/2019 *

* Diversity - The Crustaceans - crayfish, shrimp, lobsters, barnacles, crabs! 07/16/96 Gills for breathing- found underneath the cephalothorax! Large mandibles for crushing food!- jaws open side to side not up and down! 2-pairs of antennae! 2 stalked compound eyes! 5 or more pairs of walking legs with 2 large chelipeds called pinchers! Pill bugs are the most common terrestrial land crustacean!- found in damp soils 2/25/2019 *

Crustacean Example - Crayfish * 07/16/96 Crustacean Example - Crayfish 2/25/2019 *

Diversity-Centipedes and Millipedes * 07/16/96 Diversity-Centipedes and Millipedes Class Chilopoda- centipedes with one pair of legs per segment! Centipedes are carnivorous- eating snails, slugs and worms- They bite!! Class Diplopoda - millipedes with two pairs of legs per body segment! Millipedes are herbivorous - eating roots and leaves Millipedes don’t bite but they can spray a smelly-fluid from their stink glands! 2/25/2019 *

* 07/16/96 Centipede Millipede 2/25/2019 *

Diversity-The Insects * Diversity-The Insects 07/16/96 3-body parts- head-thorax-abdomen Spiracles-tracheal tubes for breathing Dorsal heart-open circulatory system 3-pairs of legs- antennae, both simple and compound eyes- A tympanum for hearing Sometimes wings- one or two pair Complete Metamorphosis- (butterflies-moths) egg-larva-pupa-adult !! Incomplete Metamorphosis-( crickets, grasshoppers) egg- nymph-molt-nymph-molt-nymph-molt-adult 2/25/2019 *

Complete Vs Incomplete Metamorphosis * 07/16/96 Complete Vs Incomplete Metamorphosis 2/25/2019 *