These most primitive members of the Animal kingdom are sessile, and do not possess any form of symmetry.
Animals that evolved from these organisms are known as eumetazoa. These organisms, which can be syconoid or leuconoid, possess bell-shaped "collar bodies" that contain a ring of microvilli and a central flagellum. These organisms utilize choanocytes to filter nutrients, and excrete waste via an osculum. They have pronged structural elements that can either be composed of calcium carbonate or silicon dioxide, called spiracles. These most primitive members of the Animal kingdom are sessile, and do not possess any form of symmetry. For 10 points, name these organisms that inhale and expel water through pores.
Animals that evolved from these organisms are known as eumetazoa.
porifera [accept sponges] &lt;AT&gt;