Transcript Animals
Kingdom: Animals Domain Eukarya Domain Bacteria AP Biology Slide show modified from: Kim Foglia @ www.explorebiology.com Blue edged slides are Kim’s Domain Archaea Domain Eukarya 2007-2008 Common ancestor Animal Characteristics Heterotrophs must ingest others for nutrients Multicellular complex bodies No cell walls allows active movement Sexual reproduction no alternation of generations no haploid gametophyte AP Biology Disagreement about phylogeny of BILATERIA Protostomia Images from Campbell and Reece AP BIOLOGY http://sps.k12.ar.us/massengale/echinoderm_notes.htm WHY ARE ECHINODERMS PLACED IN BILATERIA? Its larvae are BILATERALLY symmetrical and develop like deuterostomes! Animal Evolution Cnidaria Porifera sponges jellyfish Nematoda Platyhelminthes Annelida Mollusca Echinoderm Arthropoda flatworms roundworms mollusks segmented worms insects spiders Chordata starfish vertebrates backbone segmentation endoskeleton eucoelom body cavity bilateral symmetry tissues multicellularity AP Biology Ancestral Protist Invertebrate: Porifera Sponges Diploblastic (two germ layers) no distinct tissues or organs do have specialized cells no symmetry sessile (as adults) AP Biology food taken into each cell by endocytosis Invertebrate: Cnidaria Jellyfish, hydra, sea anemone, coral Diploblastic (two germ layers) tissues, but no organs radial symmetry predators tentacles surround gut opening GASTROVASCULAR cavity extracellular digestion release enzymes into gut cavity AP Biology Stinging cells of Cnidarians mouth tentacles sensory cell stinging cell hydra trigger stinging cell with nematocyst AP Biology discharged nematocyst undischarged nematocyst 3 KINDS OF WORMS - 3 KINDS OF COELOMS ectoderm mesoderm FLATWORMS acoelomate ROUND WORMS endoderm ectoderm mesoderm endoderm pseudocoelomate SEGMENTED WORMS ectoderm mesoderm True coelomate endoderm Invertebrate: Platyhelminthes Flatworms Triploblastic (3 germ layers) Acoelom Fluke, tapeworm, Planaria Some parasitic bilaterally symmetrical Have “less than 2” opening digestive system Flame cells-excretory Breathe through skin Open circulation Tapeworm absorb AP Biologythru skin Planaria GASTROVASCULAR CAVITY Invertebrate: Nematoda Roundworms Triploblastic Pseudocoelom bilaterally symmetrical have both mouth & anus well-developed digestive system many are parasitic Hookworm, pinworms Breathe through skin Open circulation AP Biology C. elegans Invertebrate: Annelida earthworm Segmented worms earthworms, leeches segments are not specialized bilaterally symmetrical true coelom 2 opening digestive system Breathe through skin CLOSED circulation NEPHRIDIA- excretory AP Biology fan worm leech Invertebrate: Mollusca Mollusks clams, snails, octopus bilaterally symmetrical soft bodies, many protected by hard shells true coelom OPEN circulation (except cephalopods) AP Biology Invertebrate: Arthropoda Spiders, insects, crustaceans most successful animal phylum bilaterally symmetrical segmented JOINTED APPENDAGES EXOSKELETON (chitin + protein) OPEN CIRCULATION AP Biology Arthropod groups arachnids 8 legs, 2 body parts MALPIGHIAN TUBULES spiders, ticks, scorpions crustaceans gills, 2 pairs antennae Green glands crab, lobster, barnacles, shrimp AP Biology insects 6 legs, 3 body parts Invertebrate: Echinodermata Starfish, sea urchins, sea cucumber Adults - radially symmetrical Larva-bilaterally symmetrical spiny endoskeleton Water vascular system OPEN circulation AP Biology Invertebrate quick check… Invertebrates: Porifera, Cnidaria, Platyhelminthes, Nematoda, Annelida, Mollusca, Arthropoda, Echinodermata Which phylum includes snails, clams, and octopus? Which phylum is the sponges? Which are the flatworms? …segmented worms? …roundworms? Which phylum has jointed appendages & an exoskeleton? Which two groups are radially symmetrical? Which group has no symmetry? Type of circulation most invertebrates have? Which groups are DIPLOBLASTIC? AP Biology PHYLUM = Chordata CHARACTERISTICS: NOTOCHORD PHARYNGEAL POUCHES POST ANAL TAIL DORSAL NERVE CORD hollow dorsal nerve cord becomes brain & spinal cord becomes gills or Eustachian tube pharyngeal pouches postanal becomes tail tail or tailbone becomes vertebrae notochord SUBPHYLUM = VERTEBRATA fish, amphibians, reptiles, birds, mammals VERTEBRATE CHARACTERISTICS: ALL CHORDATE CHARACTERISTICS PLUS: • • • • Bones or cartilage around a dorsal nerve cord Cranium (skull) to protect brain Endoskeleton made of bone or cartilage Closed circulatory system NOTOCHORD Notochord: flexible rod Helps organize developing cells in embryo Replaced by spinal cord in most vertebrates Becomes the vertebrae http://www.xenbase.org/xmmr/Marker_pages/notochord/Tor70stg22.jpg DORSAL NERVE CORD VENTRAL HEART Spinal cord forms along dorsal side Images from: http://www.nvo.com/jin/nssfolder/scrapbookanatomy/dorsal%20nerve%20cord.jpg http://www.ekinos.com.ar/horse.jpg PHARYNGEAL POUCHES Become gills in some vertebrates Become back of throat and inner ears in humans http://www-biol.paisley.ac.uk/courses/Tatner/biomedia/subunits/notoc.htm POST ANAL TAIL Human Embryo 32 days old http://www.evcforum.net/RefLib/EvidencesMacroevolution2_files/human_embryo.jpg Pharyngeal arches appear during 4th week Tail disappears at approximately 8 weeks 450 mya salmon, trout, sharks Vertebrates: Fish Characteristics body structure gills bony OR cartilaginous skeleton Scales, fins Lungs/swim bladder body function gills for gas exchange two-chambered heart; single loop blood circulation ectotherms reproduction external fertilization external development in AP Biology aquatic egg body Transition to Land Evolution of tetrapods Humerus Femur Pelvis Tibia Ulna Shoulder Radius Lobe-finned fish Fibula Pelvis Femur Humerus Tibia Fibula AP Biology Early amphibian Ulna Shoulder Radius Evidence suggests lobe finned fish are ancestors of amphibians http://evolution.berkeley.edu/evolibrary/images/news/tiktaalik_reconstruction.jpg TIK-TAALIK Intermediate between fish and early tetrapods Fins have basic wrist bones and simple fingers Earliest fish with a neck Discovered by Neil Shubin and Ted Daeschler in 2004 350 mya frogs salamanders toads Vertebrates: Amphibian Characteristics lung body structure buccal cavity legs (tetrapods) Thin, moist skin body function glottis closed lungs (positive pressure) & diffusion through skin for gas exchange three-chambered heart/2 loops Ectotherms Excrete UREA reproduction external fertilization external development in aquatic egg metamorphosis (tadpole to adult) AP Biology 250 mya dinosaurs, turtles lizards, snakes alligators, crocodile Vertebrates: Reptiles Characteristics Dry, scaly skin body function lungs for gas exchange three-chambered heart/2 loops (except crocodilians) ectotherms excrete URIC ACID reproduction INTERNAL fertilization external development- AMNIOTIC egg leathery embryo shell amnio chorion AP Biology allantois yolk sac IMPORTANT DEVELOPMENT AMNIOTIC EGGreptiles didn’t have to return to water to lay eggs amnion -bag of waters; the extraembryonic membrane of birds, reptiles, and mammals, which lines the chorion and contains the fetus and the amniotic fluid http://medical-dictionary.thefreedictionary.com/amnions http://media-2.web.britannica.com/eb-media/27/117227-050-E1C9ABEE.jpg 150 mya finches, hawk ostrich, turkey Vertebrates: Birds Characteristics body structure feathers & wings thin, hollow bone; flight skeleton body function very efficient lungs & air sacs four-chambered heart/2 loops endotherms excrete URIC ACID reproduction trachea lung anterior air sacs INTERNAL fertilization external development in AMNIOTIC egg posterior air sacs AP Biology 220 mya / 65 mya Vertebrates: Mammals Characteristics mice, ferret elephants, bats whales, humans body structure hair specialized teeth body function muscles contract lungs, diaphragm; negative pressure four-chambered heart/2 loops endotherms reproduction internal fertilization internal development in uterus nourishment through placenta birth live young mammary glands make milk AP Biology diaphragm contracts Vertebrates: Mammals Sub-groups monotremes egg-laying mammals duckbilled platypus, echidna marsupials pouched mammals short-lived placenta koala, kangaroo, opossum placental true placenta shrews, bats, whales, humans AP Biology 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 endothermic? Why must amphibians live near water? What reproductive adaptations made mammals very successful? What characteristics distinguish the 3 sub-groups of mammals? AP Biology