EJERCICIO 7 113-120(EDITION 14TH) 109-119 (EDITION 15TH) Filo Porifera EJERCICIO 7 113-120(EDITION 14TH) 109-119 (EDITION 15TH)
Goals for today Learn to recognized the Phylum Porifera from other animals Learn the main ‘diagnostic’ characteristics Learn about some sponges biology
These are the simplest metazoans Porifera These are the simplest metazoans Little or no tissue organization Said to belong to the cellular level of organization. No organs, no systems, no mouth, or digestive tract, only rudimentary nervous integrations. No germ layers (so neither diplo or triploblastic) Asimetric Porifera Parazoa Radiata Deuterostomia Ecdysozoa Lophotrochozoa Eumetazoa Bilateria Protostomia Cnidaria and Ctenophora Ancestral colonial choanoflagellate
Main characteristics of sponges are: Porifera Main characteristics of sponges are: Pores and canal systems (asconoid, siconoid, and leuconoid) Flagellated sponge feeding cells= choanocytes. Internal skeletons of spicules or organic fibers (spongin). Internal cavity= spongocoel that opens to an osculum
Porifera Most are marine Freshwater species are found in ponds and streams Solitary or colonial Adults are sessile
Porifera: Classification Classes: Asconoide Siconoide Leuconoide Calcarea: Spicules of calcium carbonate Needle-shaped or 3-4 rayed spicules Canal systems asconoid, siconoid, or leuconoid All marine Hexactinellida: 3D, six-rayed spicules Siliceous spicules 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 systems 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) Sycon has a syconoid canal system Marine
Porifera: Sycon Put a preserved Sycon in a petri dish for you to take a look at the shape, osculum, and spicules. There is also a model of Sycon, learn about its parts
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 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 What is the apopyle? Check your book!
Porifera: Sycon 3. Take a slide from your box with (Sycon, Grantia, or Scypha) in a longitudianal cross section you would see the following specialized cells: what are their function?
Porifera: Your Tasks Exercise 7: 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 in the micro a slide of Leucosolenia body and its spicules
Porifera: Your Tasks Exercise 7: Phylum: Porifera (sponges) Class Hexactinellida 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 Exercise 7: Phylum: Porifera (sponges) Class Demonspongiae Gemmulas (asexual reproductive structures) Gemmules are asexual reproductive structures of freshwater sponges and some marine sponges of the class Demonspogiae What is their function in reproduction?
Important Links Porifera http://bioweb.uwlax.edu/zoolab/Table-Of-Contents.htm http://faculty.uml.edu/rhochberg/hochberglab/Courses/InvertZool/Quizes/Porifera%20Quiz%201.html http://www.bumblebee.org/invertebrates/Porifera.htm