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Chapters 32--34. An introduction to the animal kingdom and its three main subkingdoms: parazoa or metazoa (sponges)—no true tissue eumetazoans —true tissues invertebrate s ( cnidaria , platyhelminthes , mollusca , annelida , arthropoda ) vertebrates ( chordata ).
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Chapters 32--34 An introduction to the animal kingdom and its three main subkingdoms: parazoa or metazoa (sponges)—no true tissue eumetazoans—true tissues invertebrates (cnidaria, platyhelminthes, mollusca, annelida, arthropoda) vertebrates (chordata)
Animals descended from colonial animal like protists called choanoflagellates Modern animals are multicellular and obtain nutrients by ingestive heterotrophic nutrition. All preferentially reproduce sexually. No cell walls are present. Cells contain centrioles.
Metazoan (no tissues) vseumetazoan (true tissues) Similar differentiated cells joined together (at least by a liquid extracellular matrix in the case of blood) and cooperating to perform a common function 4 types in animals connective transport, connect, store fibrous, elastic blood adipose nervous communication between sensory organs & muscles/glands or from neuron sensory neurons, motor neurons, interneurons muscle contract & pull against skeleton movement epithelial/endothelial cover, line, protect, secrete (glands)
Jointed appendages or none in addition to segments Crustacea (exposed gills)
Echinoderms vs chordatehttp://www.youtube.com/watch?v=HJWpisZgRI4&list=PL4B4DFE7B843CC434 start @ 8 minuteshttp://www.youtube.com/watch?v=_pH-ZxiCsbU&list=PL4B4DFE7B843CC434 allhttp://www.youtube.com/watch?v=r0Ybs2j72ZQ&list=PL4B4DFE7B843CC434 all Anus does develop From blastopore lip No notochord & dorsal Nerve ring instead of Dorsal nerve cord No postanal tail No pharyngeal gill slits
Ancestors of the chordates: dorsal nerve cord, notochord (mesodermal tissue that induces the nerve cord), pharyngeal gill slits, post-anal tail.Notochord induces formation of nervous system from ectoderm at the neural plate as the embryo folds