Kingdom Animals Domain Eukarya Domain Bacteria Domain Archaea
Kingdom: Animals Domain Eukarya Domain Bacteria Domain Archaea AP Biology Common ancestor Domain Eukarya
Animal Characteristics § Heterotrophs u must ingest others for nutrients § Multicellular u complex bodies § No cell walls u allows active movement § Sexual reproduction no alternation of generations u no haploid gametophyte u AP Biology
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 coelom body cavity bilateral symmetry tissues multicellularity AP Biology Ancestral Protist
Body Cavity How much is the digestive tract separated from the rest of the body? ectoderm mesoderm endoderm acoelomate ectoderm mesoderm endoderm pseudocoelomate pseudocoel § 3 body layers ectoderm u mesoderm u endoderm ectoderm mesoderm coelom cavity u AP Biology coelomate endoderm
Invertebrate: Porifera § Sponges u no distinct tissues or organs § do have specialized cells no symmetry u sessile (as adults) u AP Biology food taken into each cell by endocytosis
Invertebrate: Cnidaria § Jellyfish, hydra, sea anemone, coral tissues, but no organs u two cell layers u radial symmetry u predators u § tentacles surround gut opening § extracellular digestion w release enzymes into gut cavity AP Biology
Stinging cells of Cnidarians mouth tentacles sensory cell stinging cell hydra AP Biology trigger stinging cell with nematocyst discharged nematocyst undischarged nematocyst
Invertebrate: Platyhelminthes § Flatworms tapeworm, planaria u mostly parasitic u bilaterally symmetrical u § allows high level of specialization within parts of the body § now have a mouth at one end & an anus at the other! ectoderm AP Biology mesoderm endoderm
Invertebrate: Nematoda § Roundworms bilaterally symmetrical u have both mouth & anus u § well-developed digestive system u many are parasitic § hookworm AP Biology C. elegans
Invertebrate: Mollusca § Mollusks clams, snails, squid u bilaterally symmetrical (with exceptions) u soft bodies, mostly protected by hard shells u true coelem u AP Biology
Invertebrate: Annelida § Segmented worms earthworms, leeches u segments are not specialized u bilaterally symmetrical u true coelem fan worm u AP Biology leech
Invertebrate: Arthropoda § Spiders, insects, crustaceans most successful animal phylum u bilaterally symmetrical u segmented u § allows jointed appendages u exoskeleton § chitin + protein AP Biology
Arthropod groups arachnids 8 legs, 2 body parts spiders, ticks, scorpions crustaceans gills, 2 pairs antennae crab, lobster, barnacles, shrimp AP Biology insects 6 legs, 3 body parts
Invertebrate: Echinodermata § Starfish, sea urchins, sea cucumber radially symmetrical u spiny exoskeleton u AP Biology
Invertebrate quick check… Invertebrates: Porifera, Cnidaria, Platyhelminthes, Nematoda, Annelida, Mollusca, Arthropoda, Echinodermata § Which 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 are radially symmetrical? Which group has no symmetry? AP Biology
Chordata § Vertebrates fish, amphibians, reptiles, birds, mammals hollow dorsal nerve cord u internal bony skeleton u § backbone encasing spinal column § skull-encased brain becomes brain & spinal cord becomes gills or Eustachian tube pharyngeal pouches AP Biology postanal becomes tail or tailbone becomes vertebrae notochord
450 mya Vertebrates: Fish § Characteristics u body structure § bony & cartilaginous skeleton § jaws & paired appendages (fins) § scales u body function § gills for gas exchange § two-chambered heart; single loop blood circulation § ectotherms u AP Biology reproduction § external fertilization § external development in aquatic egg salmon, trout, sharks gills body
Transition to Land Evolution of tetrapods Humerus Femur Pelvis Tibia Ulna Shoulder Radius Lobe-finned fish Fibula Pelvis Femur Fibula AP Biology Humerus Tibia Early amphibian Ulna Shoulder Radius
350 mya frogs salamanders toads Vertebrates: Amphibian § Characteristics u body structure § legs (tetrapods) § moist skin u lung body function buccal cavity glottis closed § lungs (positive pressure) & diffusion through skin for gas exchange § three-chambered heart; veins from lungs back to heart § ectotherms u reproduction § external fertilization § external development in aquatic egg § metamorphosis (tadpole to adult) AP Biology
250 mya Vertebrates: Reptiles § Characteristics u dinosaurs, turtles lizards, snakes alligators, crocodile body structure § dry skin, scales, armor u body function § § u lungs for gas exchange thoracic breathing; negative pressure three-chambered heart ectotherms leathery reproduction shell embryo amnion § internal fertilization § external development in amniotic egg chorion AP Biology allantois yolk sac
150 mya finches, hawk ostrich, turkey Vertebrates: Birds § Characteristics u body structure § feathers & wings § thin, hollow bone; flight skeleton u body function § very efficient lungs & air sacs § four-chambered heart § endotherms u reproduction § internal fertilization § external development in amniotic egg § Everybody Loves Eggs! AP Biology trachea lung anterior air sacs posterior air sacs
220 mya / 65 mya Vertebrates: Mammals § Characteristics u body structure § hair § specialized teeth u mice, ferret elephants, bats whales, humans body function muscles contract § lungs, diaphragm; negative pressure § four-chambered heart diaphragm § endotherms contracts u reproduction § internal fertilization § internal development in uterus w nourishment through placenta § birth live young § mammary glands make milk AP Biology
Vertebrates: Mammals § Sub-groups u monotremes § egg-laying mammals § duckbilled platypus, echidna u marsupials § pouched mammals § short-lived placenta § koala, kangaroo, opossum u 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 subgroups of mammals? AP Biology
Any Questions? AP Biology
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