BIO SCI 94 Study Guide - Midterm Guide: Sponge, Hexactinellid, Demosponge

• School: UC-Irvine
• Department: Biological Sciences
• Course: BIO SCI 94
• Professor: Michael Clegg

Document Summary

What is a collar cell (choanocyte)? cellular level of organization: no one cell must carry on all the life activities, but different cels may become spcialized for different functions. The spiral beat of the fagellum from base to tip, causes a stream of water to flow away from its tip and brings particles toward the base of the cell. Look and behave almost exactly like the collar flagellates described earlier: know the following classification and their distinguishing characterisitics: phylum porifera, class calcaria. Leucosolenia, class hexactinellida euplectella, class demospongiae spongilla and songia. Porous with huge number of pores formed by special porocyte cells that allow water to enter the sponge and one or more large ex-current openings. Some lack body systems (asymetric) & others have concial/ cylindrical (radial) shape, others expand out into a bowl/vase-like form. Dipolblastic with 2 layers of cells (ectoderm and endoderm) rest of question on other study guide.