Bio Lab Wksht & HW Questions 34

Bio Lab Wksht - 29 Many sponges secrete glassy or calcareous skeletal structures(spicules some(such as the bath sponges lack these skeletal

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29 Many sponges secrete glassy or calcareous skeletal structures ( spicules ); some (such as the bath sponges) lack these skeletal elements and instead have skeletons comprised of flexible proteinaceous material ( spongin ). Some sponges have both spongin and spicules. Prepared slides provide examples of spicules and spongin. Sketch these structures. EUMETAZOA: Animals in the Eumetazoa are composed of definite tissues and organs ; symmetry may be radial or bilateral ; alimentary tract (if present) may have one opening ( mouth ) or two openings (mouth and anus ); bodies may be comprised of 2 ( ectoderm and endoderm ) or 3 (ectoderm, endoderm and mesoderm ) basic embryonic tissue types. There are two main branches in the Eumetazoa, the Radiata and the Bilateria RADIATA: Animals from the Radiata show primary radial symmetry and generally are diploblastic (composed of 2 main embryonic tissue layers, an outer ectoderm which forms the epidermis , and an inner endoderm which forms the gastrodermis
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This note was uploaded on 12/27/2011 for the course BSC 1020 taught by Professor Danmoon during the Fall '11 term at UNF.

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