AnimalDiversity.ppt by wangnianwu


   Objective: SWBAT explain the origin and
   diversity of animals

     What do you believe are the
       characteristics that separate animals
       from the other groups of living things?

AP Biology
     Cladogram practice and discussion
        question posted on wikispace

      Due Friday by 11:59 pm

AP Biology
             Kingdom: Animals
             Domain Eukarya

                              Domain         Domain          Domain
                              Bacteria       Archaea         Eukarya

AP Biology                                             2007-2008
                                         Common ancestor
   Animal Characteristics
    Heterotrophs
            must ingest others for nutrients
     Multicellular
            complex bodies
     No cell walls
            allows active movement
     Sexual reproduction
            Variety of organisms

AP Biology
   Early embryonic stages
     Zygote (fertilization of egg and sperm)
            solid ball stage
      Blastula
            hollow fluid-filled ball stage
               by time human embryo reaches uterus
      Gastrula
            development of primitive digestive tract
             (gut) & tissue layers

AP Biology                                      2004-
     zygote  blastula  gastrula

         How you looked
         as a gastrula…

AP Biology

    Biologists categorize the diversity of
      animals by body structure

    Helped to infer the phylogenetic
      relationship between animal groups

AP Biology
  Some animals have radial symmetry
              Like in a flower pot

(a)       Radial symmetry. The parts of a
      radial animal, such as a sea anemone
        (phylum Cnidaria), radiate from the
        center. Any imaginary slice through
         the central axis divides the animal
                 into mirror images.

        Figure 32.7a

AP Biology
  Some animals exhibit bilateral symmetry
             Or two-sided symmetry
(b)      Bilateral symmetry. A bilateral
       animal, such as a lobster (phylum
       Arthropoda), has a left side and a
       right side. Only one imaginary cut
      divides the animal into mirror-image

      Figure 32.7b

AP Biology
  Bilaterally symmetrical animals have
      A dorsal (top) side and a ventral (bottom)
      A right and left side

      Anterior (head) and posterior (tail) ends

          Cephalization - the development of a head

AP Biology
 Animal body plans
       Also vary according to the organization of
        the animal’s tissues
 Tissues
       Are collections of specialized cells isolated
        from other tissues by membranous layers

AP Biology
   Gastrulation (creation of gastrula
   (early multicellular embryo)
 zygote  blastula  gastrula
       rearranges the blastula to form
        3-layered embryo with a primitive gut

AP Biology
   Body Cavities
  In triploblastic (3 tissue layers) animals
        A body cavity may be present or absent

        Body Cavity - Fluid-filled space between the
         digestive tract and body wall
           cushions the internal organs
           enables growth and movement

AP Biology
   Primary tissue or “germ” layers
     ectoderm
            external surfaces: skin
               epidermis (skin); nails, hair & glands; tooth enamel;
                eye lens; epithelial lining of nose, mouth & rectum;
                nervous system
      endoderm
            internal lining
               epithelial lining of digestive tract & respiratory
                systems; reproductive system & urinary tract;
                digestive organs
      mesoderm
            middle tissues: muscle, blood & bone
               notochord; skeletal, muscular, circulatory, lymphatic,
                excretory & reproductive systems; lining of body
AP Biology
 A true body cavity
            Is called a coelom and is derived from

                                                                  Body covering
                                                                 (from ectoderm)

      Coelomate. Coelomates such as
 (a) annelids have a true coelom, a body
                                                                           Tissue layer
       cavity completely lined by tissue                                  lining coelom
           derived from mesoderm.                                       and suspending
                                                                         internal organs
                                                                       (from mesoderm)

                                               Digestive tract
                                             (from endoderm)

                              Figure 32.8a

AP Biology
  A pseudocoelom (false body cavity)
             Is a body cavity partially lined by tissue from
              the mesoderm
                                                                        Body covering
                                                                       (from ectoderm)

(b)     Pseudocoelomate. Pseudocoelomates                              Muscle layer
      such as nematodes have a body cavity only   Pseudocoelom           (from
         partially lined by tissue derived from                        mesoderm)

                                                     Digestive tract
                                                    (from ectoderm)

                       Figure 32.8b
AP Biology
 Organisms without body cavities

                                                         Body covering
                                                        (from ectoderm)           Tissue-
       (c)      Acoelomate. Acoelomates such as                               filled region
              flatworms lack a body cavity between                                 (from
             the digestive tract and outer body wall.                         mesoderm)

                                                            Digestive tract
                                                          (from endoderm)

    Figure 32.8c
AP Biology
   Protostome and Deuterostome

 Based on certain features seen in early
       Many animals can be categorized as having
        one of two developmental modes:
        protostome development or deuterostome

AP Biology
   Basic body plan
   Protostomes (stoma – mouth)
         “1st mouth”
         blastopore = mouth
         Invertebrates

   Deuterostomes
         “2nd mouth”
         blastopore = anus
         echinoderms & vertebrates

AP Biology                            2004-
   Mini Poster Project
     Each group will focus on a specific
        animal group
          Name
          Picture/Examples

          Body plan

              Symmetry?
              Coelom
              Cephalization
              Anything special about the animal group
              that distinguishes it from the rest

AP Biology
  Invertebrate: Porifera
                                           food taken into each
   Sponges                                cell by endocytosis

         no distinct tissues or organs
              do have specialized cells
       no symmetry
       sessile (as adults)

AP Biology
  Invertebrate: Cnidaria
   Jellyfish, hydra, sea anemone, coral
        tissues, but no organs
        two cell layers   polyp           medusa

        radial symmetry

        predators

              tentacles surround
               gut opening
              extracellular
                release enzymes
                 into gut cavity
AP Biology
                absorption by cells
                 lining gut
                      Stinging cells of Cnidarians

                                   stinging         nematocyst

       hydra                                   undischarged
                                     trigger   nematocyst

                         stinging cell
                       with nematocyst
AP Biology
    Invertebrate: Platyhelminthes
      Flatworms
             tapeworm, planaria
             mostly parasitic
             bilaterally symmetrical
               have right & left & then have
                head (anterior) end & posterior end
  Animals now
face the world
                  cephalization = development of brain
   head on!       concentration of sense organs in head
               increase specialization in body plan

 AP Biology                      acoelomate     endoderm
   Invertebrate: Nematoda
      Roundworms
            bilaterally symmetrical
            body cavity                                          C. elegans
              pseudocoelom = simple body cavity
              digestive system
                 tube running through length of body (mouth to anus)
            many are parasitic
              hookworm

AP Biology
   Invertebrate: Mollusca
     Mollusks
            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
            earthworms, leeches
            segments
              increase mobility
              redundancy in body sections
            bilaterally symmetrical
            true coelem
                                             fan worm   leech

AP Biology
   Invertebrate: Arthropoda
      Spiders, insects, crustaceans
            most successful animal phylum
            bilaterally symmetrical
            segmented
               specialized segments
               allows jointed appendages
            exoskeleton
               chitin + protein

AP Biology
    Arthropod groups
8 legs, 2 body parts
spiders, ticks, scorpions

                               gills, 2 pairs antennae
                               crab, lobster, barnacles,

AP Biology
                            6 legs, 3 body parts
   Invertebrate: Echinodermata
      Starfish, sea urchins, sea cucumber
            radially symmetrical as adults
            spiny endoskeleton
            deuterostome          loss of bilateral symmetry?

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?
    Which group has jointed appendages & an
     Which two groups have radial symmetry?
     What is the adaptive advantage of bilateral
     Which group has no symmetry?
AP Biology
    Vertebrates                                     hollow
                                                     nerve cord   becomes brai
         fish, amphibians,                                       & spinal cord
          reptiles, birds,
         internal bony
                           becomes gills or
          skeleton         Eustachian tube
              backbone encasing     pharyngeal
               spinal column         pouches

              skull-encased brain
            deuterostome                 postanal
                             becomes tail tail                    notochord
                             or tailbone
AP Biology
450 mya
                                                   salmon, trout, sharks
    Vertebrates: Fish
       Characteristics
             body structure
                bony & cartilaginous skeleton
                jaws & paired appendages (fins)
                scales
             body function
                gills for gas exchange                  body     gills
                two-chambered heart;
                 single loop blood circulation
                ectotherms
             reproduction
                external fertilization
                external development in
 AP Biology      aquatic egg
Transition to Land
Evolution of tetrapods

        Pelvis                              Ulna       Shoulder

         Fibula       Lobe-finned fish

Pelvis     Femur
                                         Humerus       Shoulder

                  Tibia                  Ulna
  AP Biology
                      Early amphibian
350 mya
    Vertebrates: Amphibian                                             salamanders
       Characteristics                 lung

                 body structure                              buccal
                   legs (tetrapods)
                   moist skin                      glottis
                 body function
                   lungs (positive pressure) &
                    diffusion through skin for gas exchange
                   three-chambered heart;
                    veins from lungs back to heart
                   ectotherms
                 reproduction
                   external fertilization
                   external development in aquatic egg
                   metamorphosis (tadpole to adult)
 AP Biology
250 mya
                                                        dinosaurs, turtles
    Vertebrates: Reptiles                               lizards, snakes
                                                        alligators, crocodile
      Characteristics
             body structure
                dry skin, scales, armor
             body function
                  lungs for gas exchange
                  thoracic breathing; negative pressure
                  three-chambered heart
                  ectotherms                      leathery   embryo
             reproduction                                                  amnion
                internal fertilization
                external development in
                   amniotic egg

 AP Biology                                                      yolk sac
150 mya
                                                             finches, hawk
    Vertebrates: Birds (Aves)                                ostrich, turkey

       Characteristics
             body structure
               feathers & wings
               thin, hollow bone;
                flight skeleton
             body function
               very efficient lungs & air sacs
               four-chambered heart
               endotherms
             reproduction                        trachea              lung
               internal fertilization
               external development in           air sacs
                amniotic egg

 AP Biology                                                      posterior
                                                                 air sacs
220 mya / 65 mya
                                                      mice, ferret
    Vertebrates: Mammals                              elephants, bats
                                                      whales, humans
      Characteristics
             body structure
               hair
               specialized teeth          muscles
             body function
               lungs, diaphragm; negative pressure
               four-chambered heart
               endotherms                         contracts
             reproduction
               internal fertilization
               internal development in uterus
                  nourishment through placenta
               birth live young
               mammary glands make milk
 AP Biology
   Vertebrates: Mammals
     Sub-groups
            monotremes
              egg-laying mammals
              lack placenta & true nipples
              duckbilled platypus, echidna
            marsupials
              pouched mammals
                 offspring feed from nipples in pouch
              short-lived placenta
              koala, kangaroo, opossum
            placental
              true placenta
                 nutrient & waste filter
              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
              the buzz!

AP Biology         2007-2008
    Animal Evolution

                 Cnidaria                  Nematoda                 Annelida               Echinodermata
    Porifera                 Platyhelminthes             Mollusca                Arthropoda                      Chordata
   sponges       jellyfish     flatworms roundworms mollusks segmented             insects    starfish       vertebrates
                                                               worms               spiders
                                                                                               body & brain
                                                   redundancy,                                size,  mobility
                                      specialization,  mobility
                                                                                         body size endoskeleton

                                                                                        coelom  digestive sys
                                                               body cavity  body complexity
                                                                            digestive & repro sys

                                          bilateral symmetry   distinct body plan; cephalization

                                   tissues   specialized structure & function,
                                             muscle & nerve tissue

               multicellularity   specialization &  body complexity
AP Biology
        Ancestral Protist
   Body Cavity                               ectoderm
 Space for organ                            endoderm
  system development
      increase digestive &
       reproductive systems                pseudocoelomate
        increase food                       ectoderm
         capacity & digestion                  mesoderm
        increase gamete                       endoderm
 Coelem
      mesoderm &
       endoderm interact
       during development                  coelomate
      allows complex                          ectoderm
       structures to develop                    mesoderm
       in digestive system                       coelom cavity
        ex. Stomach                         endoderm
AP Biology                      protostome vs. deuterostome

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