Presentation on theme: "Phylum Porifera. Kingdom: Animalia Subkingdom: Parazoa Cellular level of organization. Phylum: Porifera a. Body is perforated with 2 types of pores: 1.Ostia(inhalant."— Presentation transcript:
Kingdom: Animalia Subkingdom: Parazoa Cellular level of organization. Phylum: Porifera a. Body is perforated with 2 types of pores: 1.Ostia(inhalant or incurrent siphon):numerous,small for entering water 11.Osculum(exhalant or excurrent siphon):less in number,large in size for getting water out of body
b.Body with single cavity(Spongocoel) or (Paragastric cavity)lined with (Choanocytes)or(collar cells).
c. With 3 types of sponge structure or canal system: 1. Ascon 2. Sycon 3. Leucon
d. With internal skeleton of: 1.Spicules Calcareous Siliceous 2.Spongin fibers 3.both
Body wall Body wall
This phylum is divided into 4 classes according to: 1. The skeleton of sponge 2. The sponge structure
Class 1 :Calcarea (calcareous sponge) With calcareous spicules Ascon or sycon or leucon sponge structure Ex.1 :Lecosolenia sp. (Ascon type) Ex. 2 :Grantia sp. (Sycon type)
Class 2 : Hexactinellida (glass sponge) With siliceous spicules. Sycon sponge structure. Ex.: Euplactella sp. (Venus flower basket) Class 3 :Sclerospongia (coralline sponge) With siliceous spicules+spongin fibers covered with calcareous coat. Leucon sponge structure. Ex.: Ceratoporella sp.
Class 4 : Demospongia (normal sponges) With siliceous spicules or spongin fibers or both Ex.1 : Chalina sp. (finger sponges) Siliceous spicules+spongin fibers Ex. 2 : Euspongia sp.(bath sponge) Spongin fibers only.
Reproduction in Porifera Sexual Asexual
Sexual Parenchymula larva Amphiblastula larva Calcerea Demospongia The flagellate larva in which there is a cavity filled with gelatinous connective tissue. a free swimming larva that is a blastula with small flagellated cells in one hemisphere and large nonflagellated cells in the other
Asexual Gemmule Gemmules are internal buds found in sponges that are the result of asexual reproduction, and are a response to a hostile environment.They are resistant to desiccation (drying out), freezing, and anoxia (lack of oxygen) and can lie around for long periods of time.. Gemmules are made up of amoebocytes surrounded by a layer of spicules and can survive conditions that would kill adult sponges. When the environment becomes less hostile, the gemmule resumes growingbudsspongesasexual reproductiondesiccationanoxiaoxygen amoebocytesspicules