Characteristics of Animals All multicellular (metazoans) Eukaryotes (cells with nucleus & organelles) Ingestive heterotrophs (take in food and internally digest it) Store food reserves in the liver as glycogen copyright cmassengale

Support Systems All animals have some type of skeletal support Endoskeleton - inside and made of cartilage &/or bone Exoskeletons found in arthropods. Covers the outside of the body This limits size Must be molted making animal vulnerable to predators copyright cmassengale

Cicada Molting Exoskeleton copyright cmassengale

Support Systems Worms and echinoderms (starfish) have fluid-filled internal cavities giving them support Called hydrostatic skeletons copyright cmassengale

Movement Animals such as sponges may be sessile (attached & non-moving) Animals that move very little are said to be sedentary (clam) Animals that can move are motile Have muscular tissue to provide energy for movement copyright cmassengale

SESSILE SEDENTARY Chiton Sponge MOTILE Cheetah copyright cmassengale

Reproduction in Animals All animals are capable of sexual reproduction Some animals like sponges and earthworms are hermaphrodites producing both eggs and sperm Hermaphrodites may exchange sperm and NOT fertilize their own eggs copyright cmassengale

Leeches Exchange Sperm During Mating copyright cmassengale

Reproduction in Animals Females of some animals produce eggs, but the eggs develop without being fertilized Called Parthenogenesis New offspring will be all female Parthenogenesis occurs in some fishes, several kinds of insects, and a few species of frogs and lizards copyright cmassengale

Parthenogenesis in the Komodo Dragon copyright cmassengale

Mating and Mating Behaviors Female Beetles Mating Young Courtship Male Mating and Mating Behaviors copyright cmassengale

Levels of Organization Sponges are the ONLY animals that have just the cellular level All other animals show these levels – cell, tissue, organ, and system Cells may specialize (take own different shapes and functions) Cells are held together by cell junctions to form tissues copyright cmassengale

Levels of Organization Molecule or compound Atom Organelle Levels of Organization CELL Life begins Tissue Organ Organ system Organism copyright cmassengale

Invertebrate groups copyright cmassengale

Characteristics of Invertebrates Simplest animals Contain the greatest number of different species Most are aquatic (found in water) Do NOT have a backbone Includes sponges, cnidarians, flatworms, roundworms, annelids, mollusks, arthropods, and echinoderms copyright cmassengale

Sponge - Porifera Osculum of Sponge copyright cmassengale

Sea Anemone - Cnidaria Tentacles of Sea Anemone copyright cmassengale

More Cnidarians Brain Coral Red jellyfish copyright cmassengale

Flatworms - Platyhelminthes Marine Flatworm Planarian copyright cmassengale

Roundworms (Nematoda) and Segmented Worms (Annelida) Nematode Leech (segmented worm) copyright cmassengale

Mollusca (With and Without Shells) snail scallop octopus nudibranch nautilus copyright cmassengale

Arthropoda (insects, spiders, crustaceans, horseshoe crab) crayfish Horseshoe crab Dung beetle copyright cmassengale

Echinoderms starfish Sea fan (crinoid) Brittle star Sand dollar Sea cucumber copyright cmassengale

Vertebrate Groups copyright cmassengale

Vertebrata More complex animals Most have a backbone made up of individual bones called vertebrae From simplest to most complex, the phylum includes: fish, amphibians, reptiles, birds, and mammals copyright cmassengale

Vertebrate Backbone copyright cmassengale

Vertebrata Vertebrates have endoskeletons (internal) Some vertebrates have skeletons of cartilage (sharks, rays, and skates) Other vertebrates have skeletons of bone and cartilage (reptiles, birds, & mammals) copyright cmassengale

Bone & Cartilage in Fetus copyright cmassengale

Fish lancelet ray damselfish anglerfish copyright cmassengale

Amphibia salamander toad frog newt copyright cmassengale

Reptilia Turtle Snake Lizard Alligator copyright cmassengale

Birds - Aves hummingbird ostrich lovebirds copyright cmassengale

Mammalia copyright cmassengale

Body Areas copyright cmassengale

Surfaces Dorsal – back or upper surface Ventral – belly or lower surface Anterior – head or front end Posterior – tail or hind end opposite the head Oral surface (echinoderms) – is where the mouth is located (underside) Aboral surface (echinoderms) – is opposite the mouth (top side) copyright cmassengale

Surfaces (Most Animals) DORSAL POSTERIOR ANTERIOR VENTRAL copyright cmassengale

Surfaces (Echinoderms) ORAL ABORAL mouth copyright cmassengale

Symmetry copyright cmassengale

Body Symmetry copyright cmassengale

Body Symmetry Symmetry is the arrangement of body parts around a central plane or axis Asymmetry occurs when the body can’t be divided into similar sections (sponges) copyright cmassengale

Body Symmetry Radial symmetry occurs when body parts are arranged around a central point like spokes on a wheel (echinoderms) Most animals with radial symmetry are sessile (attached) or sedentary (move very little) copyright cmassengale

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Body Symmetry Bilateral symmetry occurs when animals can be divided into equal halves along a single plane Organisms will have right and left sides that are mirror images of each other More complex type of symmetry copyright cmassengale

Body Symmetry Animals with bilateral symmetry are usually motile Animals have an anterior and posterior ends Show cephalization (concentration of sensory organs on the head or anterior end) copyright cmassengale

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Segmentation copyright cmassengale

Segmentation Occurs whenever animal bodies are divided into repeating units or segments Found in more complex animals Earthworms show external segmentation Humans show internal segmentation (backbone) Segments may fuse (cephalothorax) copyright cmassengale

Segmentation cephalothorax copyright cmassengale

Tissues copyright cmassengale

Tissue Development Zygote (fertilized egg) undergoes rapid cell divisions called cleavage Forms a hollow ball of cells called the blastula copyright cmassengale

Blastula The blastocoel is the center cavity of the blastula with 1 germ layer (blastoderm) copyright cmassengale

Tissue Development The blastula INVAGINATES (folds inward at one point) Called Gastrulation The opening is called the blastopore The center is the primitive gut or Archenteron Archenteron blastopore copyright cmassengale

Embryonic Development copyright cmassengale

Germ Layers Form tissues, organs, & systems NOT present in sponges Ectoderm (outer) – forms skin, nerves, sense organs Endoderm (inner) – forms liver and lungs Mesoderm (middle) – forms muscles & other systems copyright cmassengale

Body Layers Sponges have NO tissues or organs, only specialized cells Cnidarians like jellyfish & coral have only two body layers & one body opening (mouth/anus) into gastrovascular cavity Cnidarians have outer epidermis & inner gastrodermis with jelly-like mesoglea between the layers copyright cmassengale

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Body Layers All worms, mollusks, arthropods, echinoderms, and vertebrates have three cell layers Ectoderm Endoderm mesoderm copyright cmassengale