AP Biology Domain Bacteria Domain Archaea Domain Eukarya Common ancestor Kingdom: Animals Domain Eukarya Slide show modified from: Kim Blue edged slides are Kim’s

AP Biology 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

Disagreement about phylogeny of BILATERIA Images from Campbell and Reece AP BIOLOGY Protostomia

WHY ARE ECHINODERMS PLACED IN BILATERIA? Its larvae are BILATERALLY symmetrical and develop like deuterostomes!

AP Biology Porifera Cnidaria Platyhelminthes spongesjellyfishflatworms roundworms Nematoda MolluscaArthropodaChordata AnnelidaEchinoderm mollusks multicellularity Ancestral Protist tissues bilateral symmetry body cavity segmentation Animal Evolution eucoelom starfishvertebrates endoskeleton segmented worms insects spiders backbone

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

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

3 KINDS OF WORMS - 3 KINDS OF COELOMS ectoderm mesoderm endoderm ectoderm mesoderm endoderm mesoderm endoderm acoelomate pseudocoelomate True coelomate FLATWORMS ROUND WORMS SEGMENTED WORMS

AP Biology 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 GASTROVASCULAR CAVITY absorb thru skin Tapeworm Planaria

AP Biology 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

AP Biology Invertebrate: Annelida Segmented worms  earthworms, leeches  segments are not specialized  bilaterally symmetrical  true coelom  2 opening digestive system  Breathe through skin  CLOSED circulation  NEPHRIDIA- excretory fan wormleech earthworm

AP Biology 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 insects 6 legs, 3 body parts crustaceans gills, 2 pairs antennae Green glands crab, lobster, barnacles, shrimp arachnids 8 legs, 2 body parts MALPIGHIAN TUBULES spiders, ticks, scorpions

AP Biology 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…  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? Invertebrates: Porifera, Cnidaria, Platyhelminthes, Nematoda, Annelida, Mollusca, Arthropoda, Echinodermata

postanal tail notochord hollow dorsal nerve cord pharyngeal pouches PHYLUM = Chordata becomes brain & spinal cord becomes vertebrae becomes gills or Eustachian tube becomes tail or tailbone CHARACTERISTICS: NOTOCHORD PHARYNGEAL POUCHES POST ANAL TAIL DORSAL NERVE CORD

SUBPHYLUM = VERTEBRATA 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 fish, amphibians, reptiles, birds, mammals

NOTOCHORD Notochord: flexible rod Helps organize developing cells in embryo Replaced by spinal cord in most vertebrates Becomes the vertebrae

DORSAL NERVE CORD VENTRAL HEART Spinal cord forms along dorsal side Images from:

PHARYNGEAL POUCHES Become gills in some vertebrates Become back of throat and inner ears in humans

POST ANAL TAIL

Human Embryo 32 days old Pharyngeal arches appear during 4 th week Tail disappears at approximately 8 weeks

AP Biology Vertebrates: Fish salmon, trout, sharks 450 mya  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

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

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

AP Biology lung buccal cavity glottis closed Vertebrates: Amphibian  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) frogs salamanders toads 350 mya

AP Biology Vertebrates: Reptiles 250 mya dinosaurs, turtles lizards, snakes alligators, crocodile embryo leathery shell chorion allantois yolk sac amnion  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

amnion -bag of waters; the extraembryonic membrane of birds, reptiles, and mammals, which lines the chorion and contains the fetus and the amniotic fluid IMPORTANT DEVELOPMENT AMNIOTIC EGG- reptiles didn’t have to return to water to lay eggs

AP Biology 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 150 mya finches, hawk ostrich, turkey trachea anterior air sacs lung posterior air sacs

AP Biology 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 220 mya / 65 mya mice, ferret elephants, bats whales, humans muscles contract diaphragm contracts

AP Biology 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?