TAMU Biology 112 Lab Practical 2 Exam Questions and Answers 100% Pass

TAMU Biology 112 Lab Practical 2 Exam Questions and Answers 100% Pass Phylum Porifera - Answer- No true tissues Asymmetrical symmetry Taxa: -Silicea (glass sponges) -Calcarea (rest of sponges) Osculum - Answer- Water exit in sponges Spicules - Answer- -Skeletal components of sponges made of silica, calcite or spongin -Produced by amoebocytes Choanocytes - Answer- Spong's filter-feeding cells Phylum Cnidaria - Answer- Diploblastic Radially symmetrical Cnidocytes Classes: -Anthozoa -Scyphozoa -Cubozoa -Hydrozoa Two body plans of Phylum Cnidaria - Answer- Mobile medusa (sexual reproduction) Sessile polyp (asexual reproduction) Cnidocytes - Answer- Specialized cells that contain stinging organelles called nematocysts Gastrovascular cavity in cnidarians - Answer- Serves as both a gut and a hydrostatic skeleton Single opening serves as both mouth and anus Class Hydrozoa - Answer- Alternate between a dominant polyp stage and less common medusa form (Physalia pictured) Obelia, Hydra, Physalia Class Scyphozoa - Answer- Dominant medusa form, reduced polyp (Aurelia pictured) Jellies Class Anthozoa - Answer- Exist only as polyps Sessile, often colonial Sea anemones and corals Reproduce asexually by fragmentation or sexually by production of gametes Class Cubozoa - Answer- Box-shaped medusa Box jellies, sea wasps Unranked clade Ecdysozoa - Answer- Bilaterally symmetrical Triploblastic Protostome Ecdysis: molt Phyla: -Nematoda -Arthropoda Protostome - Answer- Develop from splitting of embryonic mesoderm Schizocoelous coelom Determinate cell division Spiral cleavage Blastopore becomes mouth Deuterostome - Answer- Develop from mesodermal outpocketings of embryonic gut (archenteron) Enterocoelous coelom Indeterminate cell division Radial cleavage Blastopore becomes anus Acoelomate - Answer- Lack a cavity between the digestive tract and outer body wall Pseudocoelomate - Answer- Body partially lined with mesoderm Coelomate - Answer- Phylum Nematoda - Answer- Complete digestive system Separate sexes Pseudocoelomate Longitudinal muscles against a fluid-filled psuedocoel = thrashin