113-120(EDITION 14TH) 109-119 (EDITION 15TH) Phylum Porifera 113-120(EDITION 14TH) 109-119 (EDITION 15TH)

Goals for today Learn to recognized the Phylum Porifera from other animals Learn the main ‘diagnostic’ characteristics, structures, and their function Learn about some sponges biology

Phylum Porifera Most are marine Freshwater species are found in ponds and streams Solitary or colonial Adults are sessile and benthic

These are the simplest metazoans (multi cellular organisms) Porifera = "pore bearer" Porifera Parazoa Radiata Deuterostomia Ecdysozoa Lophotrochozoa Eumetazoa Bilateria Protostomia Cnidaria and Ctenophora Ancestral colonial choanoflagellate These are the simplest metazoans (multi cellular organisms) No organs, no mouth, no nervous, digestive or circulatory system, only rudimentary nervous integrations. Little or no tissue organization No germ layers (so neither diplo- or triploblastic) Two thin layers of cells (Epidermis and Endodermis) Some have radial symmetry some do not

Main characteristics of sponges are: Phylum Porifera Main characteristics of sponges are: Internal skeletons of spicules or organic fibers (spongin). Pores and canal systems (asconoid, siconoid, and leuconoid) Internal cavity= spongocoel that opens to an osculum

Phylum Porifera Flagellated sponge feeding cells= choanocytes. By cooperatively moving their flagella, choanocytes generate a flow of water through the sponges pores, into the spongocoel, and out through the osculum.

Phylum Porifera Feeding Behavior http://www.youtube.com/watch?feature=player_embedded&v=RmPTM965-1c

Porifera: Classification Classes: Calcarea: Spicules of calcium carbonate Needle-shaped or 3-4 rayed spicules Canal systems asconoid, siconoid, or leuconoid All marine Hexactinellida (Glass sponges): 3D, six-rayed spicules Siliceous spicules (SiO2)forming a network Body often cylindrical or funnel-shaped. Canal systems siconoid or leuconoid All marine, and most deep water spp. Demospongiae: Siliceous spicules (not six-rayed), spongin or both Canal system leuconoid One family freshwater, most marine Most sponges belong to this class

Porifera: Your Tasks Exercise 7: Phylum: Porifera (sponges) Class Calcarea Genus: Sycon (=Scypha, Grantia)

Porifera: Sycon 2. Take a slide from your box with (Sycon, Grantia, or Scypha) this is a cross section cut: identify the incurrent canal, spongocoel, and the radial canal Water enters the incurrent canals and passes through minute openings called? ____________ Check your book for answers!

Porifera: Sycon What is the apopyle? Check your book!

Porifera: Sycon 3. Take a slide from your box with (Sycon, Grantia, or Scypha) in a longitudinal cross section you would see the following specialized cells: what are their function?

Porifera: Your Tasks Phylum: Porifera (sponges) Class Calcarea Genus: Leucosolenia Leucosolenia has an asconoide canal system

Porifera: Leucosolenia Try to find the osculum. This is a colonial species of tubular individuals in various stages of development osculum

Porifera: Leucosolenia 2. Look into the microscope a slide of Leucosolenia body and its spicules

Porifera: Your Tasks Phylum: Porifera Class Hexactinellida (Glass sponges) Genus: Euplectella

Porifera: Your Tasks 1. Look at preserved specimens of Euplectella Some species of Euplectella have a commensal relationship with a shrimp species. A young male and female shrimp enter the central cavity and live there. As they grow they become too large to escape through the sieve-like covering of the osulum, and so spend their entire life inside the sponge.

Porifera: Your Tasks Phylum: Porifera (sponges) Class Demospongiae Gemmulas (asexual reproductive structures) -Gemmules are asexual reproductive structures of freshwater sponges and some marine sponges of the class Demospongiae. -Made up of amoebocytes surrounded by a layer of spicules and can survive conditions that would kill adult sponges. What is their function in reproduction?

Important Links Porifera http://faculty.uml.edu/rhochberg/hochberglab/Courses/InvertZool/Quizes/Porifera%20Quiz%201.html http://www.bumblebee.org/invertebrates/Porifera.htm http://bioweb.uwlax.edu/zoolab/Table-Of-Contents.htm