Classification

A Very Diverse Kingdom

Kingdom Animalia CharacteristicsAll animals share the following characteristicsEukaryoticMulticellularReproduce sexuallyHeterotrophicMotile, at least for part of their life2Animals are taxonomically grouped based on three main features:Number of body layersType of Body cavityBody Symmetry

Kingdom Animalia Features3The 3 main layers appear very early in embryonic development. In humans the layers are:Ectoderm skin, nervesMesoderm muscles, blood, kidneysEndoderm lungs, liver, gut lining

Feature 1: Number of body layers4The two main types of body cavities are:Coelomates have a fluid filled body cavity that supports organ systemsAcoelomates lack a fluid filled body cavity like flatwormsFeature 2: Type of Body Cavity5

Text - Page 497The three main types of symmetry are:Bilateral can be cut into two mirror images through a central line.Radial body is organized around a central axis. They are symmetrical around any central cut.Asymmetry no distinctive symmetryFeature 3: Body Symmetry78

TopBottomBackFront8Animal PhylaAnimalia phyla are spilt into two major groups based on the presence or absence of a spinal cord and vertebraNon-chordates or invertebratesChordates or vertebrates

9These are animals without a notochord (backbone)There are eight phyla of invertebratesPorifera, SpongesCnidarians, jellyfishPlatyhelminthes, Flatworms Annelids, segemented wormspinwormNematoda, RoundwormsMollusca, snails, clamsEchinoderms, starfishArthropods, insects, crabsspiders

Invertebrate Phyla

101. Porifera: Spongeslack any definite symmetrySponges are the simplest animals, lack defined tissues and organsAre hermaphroditicFertilized eggs become free-swimming larvae, which then attach to the ocean floor, metamorphose and become fixed in one place.

112. Cnidarians: Jellyfish and CoralsHave radial symmetryreproduce both sexual and asexuallyHave tentacles with stinging cells that they use to capture food.

123. Platyhelminthes: Flatworms Have bilateral symmetry.

Free living worms are hermaphroditic, they generate a reproductive system only during breeding season.Can be free-living or parasites.

134. Nematodes: RoundwormsHave bilateral symmetry.Have long thin, round worm like bodiesMost are free-living, however some are parasitic and can cause major health concerns.Simplest organisms to have a complete digestive tract.

145. Annelida: Segmented WormsHave bilateral symmetry Have round, segmented bodies which is beneficial for movement, can move different parts at a time, increases flexibility.Have a coelom

156. Mollusca: Snails, Clams, SquidHave bilateral symmetryAre coelomicThey are soft-bodied animals. Most cover their body with a shell for protection.

16Have radial symmetryHave spiny outer covering for protectionMove by changing water pressure inside tubes in the armsCan be stationary or burrowingHave a coelom

7. Echinodermata: Starfish

17Have bilateral symmetry. Ecologically important part of food chains due to their abundant numbersHave a coelom, including simple respiratory, circulatory and excretory systemsThere are four group of arthropods: Arachnids (spiders)Centipedes & MillipedesCrustaceans (crabs, shrimp)Insects8. Arthropoda: Insects and Spiders

18