Life Science - A layer in the sponge of so-called collar cells or choanocytes, each with one flagellum pointing toward the atrial cavity and surrounded by a ring of short appendages called
Sponge Structure and Function - Advanced | CK-12 Foundation
a sponge makes the top 10 : BioBlog: University of Waikato
Text book of zoology. Zoology. Fig. 73. Collar cells of aSponge. fc collar.. Fig. 74. Various forms of Sponges; diagrammatic longitudinal sections, o osculum, p pores.—Orig. saccular evaginations of the exhalent