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Animal Kingdom. Characteristics. Heterotrophic, multicellular , eukaryotes Mobile (most) Require oxygen for cellular respiration. Evolutionary Past. Common ancestor (700 million yrs ago) colonial, flagellated, protist
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Characteristics • Heterotrophic, multicellular, eukaryotes • Mobile (most) • Require oxygen for cellular respiration
Evolutionary Past • Common ancestor (700 million yrs ago) • colonial, flagellated, protist • Cell folded in on itself creating a digestive cavity and giving rise to first animal
Nerve cells develop separating sponges (Porifra) from the rest of the animal phyla
Radial symmetry separates the Cnidaria phyla from the rest which exhibit bilateral symmetry
Other phyla separated by similarities in embryonic development • protostomes (invertebrates) • deuterostomes (vertebrates [chrodata]; and echinodermata b/c of similar embryonic development)
Protostomes include: • Platyhelminthes (flatworms) • Rotifera (rotifers) • Mollusca (molluscs) • Annelida (segmented worms) • Nemtoada (round worms) • Arthropoda (insects, jointed limbs)
Cell Specialization • Stem cells (undifferentiated cells) are able to develop into all the specific types of cells (differentiated cells) found in an organism. • Tissues are groups of differentiated cells acting together
Distinguishing Phyla • Germ layer similarites • 3 embryonic germ layers: • Ectoderm (outer layer) • Mesoderm (middle layer) • Endoderm (inner layer) • Not all phyla have all layers • Ex. Cnidera do not have a mesoderm
Ectoderm develops into: • Shells, scales, feathers, hair, nails Mesoderm develops into: • Circulatory, reproductive, excretory, muscular systems, and body cavity Endoderm develops into: • Inner lining of gut and respiratory system
Distinguishing Phyla • Presence of a body cavity (coelum) or not • Ex. Flatworms (Platyhelminthes) do not have a coelum
HWK • Read pg 96-99 • Questions #1,3,4,5