Kingdom Animals Domain Eukarya Domain Eubacteria AP Biology
Kingdom: Animals Domain Eukarya Domain Eubacteria AP Biology Domain Archaea Domain Eukarya 2007 -2008 Common ancestor
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 Echinodermata Arthropoda flatworms roundworms mollusks segmented worms redundancy, segmentation specialization, mobility insects spiders starfish Chordata vertebrates body & brain backbone size, mobility body size endoskeleton coelom digestive sys radial body cavity body complexity digestive & repro sys bilateral symmetry tissues multicellularity AP Biology Ancestral Protist distinct body plan; cephalization specialized structure & function, muscle & nerve tissue specialization & body complexity bilateral
Body Cavity § Space for organ system development u increase digestive & reproductive systems § increase food capacity & digestion § increase gamete production § Coelem mesoderm & endoderm interact during development u allows complex structures to develop in digestive system acoelomate ectoderm mesoderm endoderm pseudocoel u § ex. stomach AP Biology coelomate ectoderm mesoderm coelom cavity endoderm protostome vs. deuterostome
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 polyp u two cell layers u radial symmetry u predators u § tentacles surround gut opening § extracellular digestion w release enzymes AP Biology into gut cavity w absorption by cells lining gut medusa
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 u u u tapeworm, planaria mostly parasitic bilaterally symmetrical § have right & left & then have head (anterior) end & posterior end Animals now w cephalization = development of brain face the world w concentration of sense organs in head on! § increase specialization in body plan ectoderm AP Biology acoelomate mesoderm endoderm
Invertebrate: Nematoda § Roundworms u u bilaterally symmetrical body cavity C. elegans § pseudocoelom = simple body cavity § digestive system w tube running through length of body (mouth to anus) u many are parasitic § hookworm AP Biology
Invertebrate: Mollusca § Mollusks u u slugs, snails, clams, squid bilaterally symmetrical (with exceptions) soft bodies, mostly protected by hard shells true coelem § increases complexity & specialization of internal organs AP Biology
Invertebrate: Annelida § Segmented worms u u earthworms, leeches segments § increase mobility § redundancy in body sections u u AP Biology bilaterally symmetrical true coelem fan worm leech
Invertebrate: Arthropoda § Spiders, insects, crustaceans u u u most successful animal phylum bilaterally symmetrical segmented § specialized segments § allows jointed appendages u exoskeleton § chitin (carbohydrate) + 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 u u u AP Biology radially symmetrical as adults spiny endoskeleton loss of bilateral symmetry? deuterostome
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 have radial symmetry? § What is the adaptive advantage of bilateral symmetry? AP Biology § Which group has no symmetry?
- Slides: 15