Kingdom: Animals Domain Eukarya Slide show modified from: Bacteria Archaea Eukarya Common ancestor Slide show modified from: Kim Foglia @ www.explorebiology.com Blue edged slides are Kim’s 2007-2008

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

Invertebrate: Porifera food taken into each cell by endocytosis Sponges Diploblastic (two germ layers) no distinct tissues or organs do have specialized cells no symmetry sessile (as adults)

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

Stinging cells of Cnidarians hydra stinging cell with nematocyst trigger discharged nematocyst undischarged tentacles mouth sensory cell

3 KINDS OF WORMS - 3 KINDS OF COELOMS ectoderm mesoderm FLATWORMS endoderm acoelomate ectoderm mesoderm ROUND WORMS 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 Planaria GASTROVASCULAR CAVITY absorb thru skin

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 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 fan worm leech

Invertebrate: Mollusca Mollusks clams, snails, octopus bilaterally symmetrical soft bodies, many protected by hard shells true coelom OPEN circulation (except cephalopods)

Invertebrate: Arthropoda Spiders, insects, crustaceans most successful animal phylum bilaterally symmetrical segmented JOINTED APPENDAGES EXOSKELETON (chitin + protein) OPEN CIRCULATION

Arthropod groups arachnids crustaceans insects 8 legs, 2 body parts MALPIGHIAN TUBULES spiders, ticks, scorpions crustaceans gills, 2 pairs antennae Green glands crab, lobster, barnacles, shrimp 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

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?

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 becomes vertebrae postanal tail becomes tail or tailbone 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 Pharyngeal arches appear during 4th week http://www.evcforum.net/RefLib/EvidencesMacroevolution2_files/human_embryo.jpg Pharyngeal arches appear during 4th week Tail disappears at approximately 8 weeks

Vertebrates: Fish Characteristics body structure body function 450 mya salmon, trout, sharks Vertebrates: Fish Characteristics body structure 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 aquatic egg gills body

Transition to Land Evolution of tetrapods Evidence suggests Tibia Femur Fibula Humerus Shoulder Radius Ulna Pelvis Lobe-finned fish Early amphibian Evidence suggests lobe finned fish are ancestors of amphibians

TIK-TAALIK Intermediate between fish and early tetrapods 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

Vertebrates: Amphibian 350 mya frogs salamanders toads Vertebrates: Amphibian lung buccal cavity glottis closed Characteristics body structure legs (tetrapods) Thin, moist skin body function 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)

Vertebrates: Reptiles 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 embryo leathery shell chorion allantois yolk sac amnion

IMPORTANT DEVELOPMENT AMNIOTIC EGG- reptiles 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

Vertebrates: Birds Characteristics body structure body function 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 INTERNAL fertilization external development in AMNIOTIC egg trachea anterior air sacs lung posterior

Vertebrates: Mammals Characteristics body structure body function 220 mya / 65 mya mice, ferret elephants, bats whales, humans Vertebrates: Mammals Characteristics body structure hair specialized teeth body function 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 muscles contract diaphragm contracts

Vertebrates: Mammals Sub-groups monotremes marsupials placental egg-laying mammals duckbilled platypus, echidna marsupials pouched mammals short-lived placenta koala, kangaroo, opossum placental true placenta shrews, bats, whales, humans

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?