4 Body Cavity Space for organ system development Coelem acoelomateectodermSpace for organ system developmentincrease digestive & reproductive systemsincrease food capacity & digestionincrease gamete productionCoelemmesoderm & endoderm interact during developmentallows complex structures to develop in digestive systemex. stomachmesodermendodermpseudocoelomateectodermmesodermendodermpseudocoelcoelomateectodermmesodermcoelom cavityendodermprotostome vs. deuterostome
5 Invertebrate: Porifera food taken into each cell by endocytosisSpongesno distinct tissues or organsdo have specialized cellsno symmetrysessile (as adults)
6 Invertebrate: Cnidaria Jellyfish, hydra, sea anemone, coraltissues, but no organstwo cell layersradial symmetrypredatorstentacles surround gut openingextracellular digestionrelease enzymes into gut cavityabsorption by cells lining gutpolypmedusa
7 Stinging cells of Cnidarians hydrastinging cellwith nematocysttriggerdischargednematocystundischargedtentaclesmouthsensorycell
8 Invertebrate: Platyhelminthes Flatwormstapeworm, planariamostly parasiticbilaterally symmetricalhave right & left & then have head (anterior) end & posterior endcephalization = development of brainconcentration of sense organs in headincrease specialization in body planAnimals now face the world head on!ectodermmesodermendodermacoelomate
9 Invertebrate: Nematoda Roundwormsbilaterally symmetricalbody cavitypseudocoelom = simple body cavitydigestive systemtube running through length of body (mouth to anus)many are parasitichookwormC. elegans
10 Invertebrate: Mollusca Mollusksslugs, snails, clams, squidbilaterally symmetrical (with exceptions)soft bodies, mostly protected by hard shellstrue coelemincreases complexity & specialization of internal organs
11 Invertebrate: Annelida Segmented wormsearthworms, leechessegmentsincrease mobilityredundancy in body sectionsbilaterally symmetricaltrue coelemfan wormleech
13 Arthropod groups arachnids crustaceans insects 8 legs, 2 body parts spiders, ticks, scorpionscrustaceansgills, 2 pairs antennaecrab, lobster, barnacles, shrmpinsects6 legs, 3 body parts
14 Invertebrate: Echinodermata Starfish, sea urchins, sea cucumberradially symmetrical as adultsspiny endoskeletondeuterostomeloss of bilateral symmetry?
15 Invertebrate quick check… Invertebrates: Porifera, Cnidaria, Platyhelminthes, Nematoda, Annelida, Mollusca, Arthropoda, EchinodermataWhich group includes snails, clams, and squid?Which group is the sponges?Which are the flatworms?…segmented worms?…roundworms?Which group has jointed appendages & an exoskeleton?Which two groups have radial symmetry?What is the adaptive advantage of bilateral symmetry?Which group has no symmetry?Which group includes snails, clams, and squid? MollusksWhich group is the sponges? PoriferaWhich are the flatworms? Platyhelminthes…segmented worms? Annelids…roundworms? NematodesWhich group has jointed appendages & an exoskeleton? ArthropodsWhich two groups have radial symmetry? Cnidaria, EchinodermWhat is the adaptive advantage of bilateral symmetry? cephalizationWhich group has no symmetry? Profiera
16 Oh, look… your first baby picture! ChordataVertebratesfish, amphibians, reptiles, birds, mammalsinternal bony skeletonbackbone encasing spinal columnskull-encased braindeuterostomehollow dorsalnerve cordbecomes brain & spinal cordbecomes gills or Eustachian tubeOh, look… your first baby picture!pharyngealpouchesbecomes vertebraepostanaltailbecomes tail or tailbonenotochord
17 Vertebrates: Fish Characteristics body structure body function 450 myasalmon, trout, sharksVertebrates: FishCharacteristicsbody structurebony & cartilaginous skeletonjaws & paired appendages (fins)scalesbody functiongills for gas exchangetwo-chambered heart; single loop blood circulationectothermsreproductionexternal fertilizationexternal development in aquatic egggillsbody
18 Transition to Land Evolution of tetrapods Lobe-finned fish TibiaFemurFibulaHumerusShoulderRadiusUlnaPelvisLobe-finned fishEarly amphibian
19 Vertebrates: Amphibian 350 myafrogssalamanders toadsVertebrates: AmphibianlungbuccalcavityglottisclosedCharacteristicsbody structurelegs (tetrapods)moist skinbody functionlungs (positive pressure) & diffusion through skin for gas exchangethree-chambered heart; veins from lungs back to heartectothermsreproductionexternal fertilizationexternal development in aquatic eggmetamorphosis (tadpole to adult)
20 Vertebrates: Reptiles 250 myadinosaurs, turtleslizards, snakesalligators, crocodileVertebrates: ReptilesCharacteristicsbody structuredry skin, scales, armorbody functionlungs for gas exchangethoracic breathing; negative pressurethree-chambered heartectothermsreproductioninternal fertilizationexternal development in amniotic eggembryoleatheryshellchorionallantoisyolk sacamnion
21 Vertebrates: Birds (Aves) 150 myafinches, hawkostrich, turkeyVertebrates: Birds (Aves)Characteristicsbody structurefeathers & wingsthin, hollow bone; flight skeletonbody functionvery efficient lungs & air sacsfour-chambered heartendothermsreproductioninternal fertilizationexternal development in amniotic eggtracheaanteriorair sacslungposterior
22 Vertebrates: Mammals Characteristics body structure body function 220 mya / 65 myamice, ferretelephants, bats whales, humansVertebrates: MammalsCharacteristicsbody structurehairspecialized teethbody functionlungs, diaphragm; negative pressurefour-chambered heartendothermsreproductioninternal fertilizationinternal development in uterusnourishment through placentabirth live youngmammary glands make milkmusclescontractdiaphragmcontracts
24 Vertebrate quick check… Which vertebrates lay eggs with shells?Which vertebrates are covered with scales?What adaptations do birds have for flying?What kind of symmetry do all vertebrates have?Which vertebrates are ectothermic and which are endothermicWhy must amphibians live near water?What reproductive adaptations made mammals very successful?What characteristics distinguish the 3 sub-groups of mammals?
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