NematodaNematodaNematode Diets and MouthsTrichinella spiralisPhylum MolluscaPhylum MolluscaImportant Mollusk FeaturesMollusk Body DesignsCampbell Fig.’s 18.9B-FMollusk diversityMollusk diversityGiant Squid!Complex Squid BehaviorSegmentationPhylum AnnelidaTypes of annelidsEarthwormsPolychaetesPolychaete DiversityLeech AnatomyLeech DiversityArthropodaDiversity of ArthropodaArthropod CharacteristicsCuticleCampbell fig 18.12AArthropod GroupsArthropoda diversity compare Campbell Fig. 18.12B-ECommon Features of insectsIncomplete MetamorphosisComplete Metamorphosislarval stages specialized for eating and look different from the adult formsInsect DiversityEchinodermataApparent Radial Symmetry Fig. 18.14AEchinoderm HabitatWater Vascular SystemTube Feet of Sea StarStarfish AnatomyCampbell Fig. 18.14AReproductionSea Stars or StarfishCampbell Fig. 18.14ASea urchins and Sand dollarscompare Campbell Fig. 18.14CBrittle or Serpent StarsFeather Stars or Sea LiliesSea CucumbersNematodaRound wormsFeeding and ParasitismNematoda• Have pseudocoelom• Live in many environments• Parasitic• Important decomposers• Covered with cuticle•Trichinella spiralis see fig 18.8BNematode Diets and Mouthspredatorsmicrobivore plant parasitesTrichinella spiralisFigure 18.8• Juvenile worms live in undercooked pork• You eat them - the develop into adults in your intestines• They find their way into your heart muscle and other muscle causing damage•Cook your meat!Phylum MolluscaSoft bodied animals with shellsAnd diverse body formsPhylum Mollusca• Name means “soft-shelled nut”• Snail, clams, oysters, octopuses and squids• Feeding habits:– Scrapers and suspension feeders (rarely, carnivores)Important Mollusk Features• muscular foot - posterior, ventral, locomotory• mantle -dorsal epidermis that makes the shell– also encloses the body in a mantle cavity– ciliated mantle cavity helps with respiration and sometimes feeding• radula -tongue-like scraper used for feedingCampbell 18.9Mollusk Body DesignsCampbell Fig.’s 18.9B-FMollusk diversitychitonsMollusk diversitySquidSea slugNautilusGiant Squid!Artituthus can be 30 ft+Complex Squid Behavior• shell reduced to pen • mood and camouflage colors• ink for concealmentSegmentation• Most animals have segmented bodies• Subdivision of body into repeatedparts– Nervous, circulatory,excretory organs• Provides flexibility, and mobilityPhylum AnnelidaSegmented WormsTypes of annelids• Earthworms -Terrestrial soil worms• Polychaetes -Marine sand worms-have appendages• Leeches-fresh water -parasitic!–Hirudo medicinalisEarthworms• Soil annelids• Process soil by digesting the organic matter there•Improve its texture• See the segmentsCampbell 18.10Polychaetessegment or repeating body unit has appendages and bristlesPolychaete Diversitypaper tube worm(filter-feeder)lug worm(deposit-feeder)sand worm(carnivore)surface deposit-feederLeech AnatomyLeech DiversityArthropodaThe Most Successful PhylumDiversity of Arthropoda• > 2,000,000 species (estimated)– our worst pests and valuable helpersArthropod Characteristics• jointed appendages– Walking, feeding, reproduction• chitinous cuticle thickened to exoskeleton• Molting– Shed old skin to allow body growth• SEGMENTS ARE FUSED!Cuticle• mainly chitin– tough, flexible, covering– stiffened with calcium carbonate in some arthropods– permeable but resists chemicals– waterproofed with waxes in insects• protection, support, muscle attachmentCampbell fig 18.12AArthropod Groups•Horseshoe crabs• Arachnids•Crustaceans• Centipedes and millipedes•InsectsArthropoda diversity compare Campbell Fig. 18.12B-EArachnidsMillipedeCrustaceaHorseshoe crabCommon Features of insects• Three part body– Head - antenna, eyes, mouthparts–Thorax -legs and wings–Abdomen18.13AIncomplete Metamorphosis• Young resemble adults with different body proportions• Wingpads visible in larvaedamselflywing padsmayflywing padsComplete Metamorphosislarval stages specialized for eating and look different from the adult formslarvaepupaadulteggbeetleadultlarva pupaadultadulteggsantInsect DiversityDragon and damselfliesMosquitosMothsBees, waspsWaterstridersBeetlesEchinodermataSpiny-skinnedSea AnimalsApparent Radial SymmetryFig. 18.14Alike spokes of a wheelsea starEchinoderm Habitat• entirely marine• larvae are planktonic and Bilateral• adults are entirely benthic– but most adults can crawl, and tend back toward bilateral symmetryWater Vascular System• unique to echinoderms• used for locomotion and food-gatheringComponents:• Water filled canals• tube feetTube Feet of Sea Starequipped with: internal ampulla,valves, and many tiny musclesconnector to a radial canalStarfish AnatomyCampbell Fig. 18.14Abony internal skeletonpyloric stomachelements of water vascular systemcardiac stomachReproduction• mostly sexual but sea stars can regenerate severed arms • some kinds can break apart and re-grow into twosea star, regenerating armsSea Stars or StarfishCampbell Fig. 18.14ASea urchins and Sand dollarscompare Campbell Fig. 18.14Csand dollarsea urchinsome have poisonous spinesBrittle or Serpent StarsScavengers and passive suspension-feedersFeather Stars or Sea Liliespassive filter-feedersSea Cucumberstube