Welcome to…. THE ANIMAL KINGDOM Multicellular heterotrophs with tissues

 Porifera – sponges  Cnidaria -- jellyfish, hydras, anemones, etc.

Platyhelminthes-- flatworms Nematoda– roundworms Annelida-- segmented worms and leeches

Mollusca-- clams, snails, octopuses, squid Arthropoda-- insects, crustaceans, arachnids

 Echinodermata-- starfish, brittlestars, sand dollars  Chordata– vertebrates: fish, amphibians, reptiles, birds, mammals

Animal Characteristics Multicellular heterotrophs that:  have a body cavity  do not have cell walls (unlike plants, fungi, and bacteria)  have tissues-- groups of cells that work together/recognize each other  have tissues arranged into organs.

Animals are sometimes classified according to their symmetry (complex animals have more sophisticated symmetry)  Asymmetry— no apparent symmetry (many sponges)  Spherical symmetry —no top, bottom, left, right, front, or back (embryological stages-- morula, etc.)  Radial symmetry — have top and bottom (starfish, jellyfish, et.al.)  Bilateral symmetry— have front, back, right, left, top, bottom (worms, humans, dogs)

Directions on a bilaterally- symmetrical animal DORSAL ANTERIOR POSTERIOR VENTRAL LATERAL: toward the side

Animals are sometimes classified by degree of cephalization Cephalization: anterior brain and sensory organs Allows for more efficient concentration of effort in one region rather than having the entire body fulfill that function. Can therefore identify threats, or opportunities, more quickly.

Animals are sometimes classified as:  Invertebrates— no backbone  Vertebrates— have backbone /dorsal nerve cord

Animals are sometimes classified by their body cavity: (coelom = body cavity)  Acoelomates —no body cavity (some sponges have b.c.)  Pseudocoelomates —have fold that functions as b.c.  Coelomates —have a true body cavity for organs