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Phylum Porifera

Phylum Porifera. The Sponges. Phylum Porifera Overview. Most primitive of the multicellular animals There is some debate if sponges are complex colonial protozans and not metazoans. Sponges Over 7,000 species, approximately 40 species that occur in local waters

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Phylum Porifera

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  1. Phylum Porifera The Sponges Phylum Porifera

  2. Phylum Porifera Overview • Most primitive of the multicellular animals • There is some debate if sponges are complex colonial protozans and not metazoans. • Sponges • Over 7,000 species, approximately 40 species that occur in local waters • 2% of all sponges are freshwater, none are terrestrial Phylum Porifera

  3. Phylum Porifera Overview • Sponges occur in shallow water habitats and vary widely in size (up to 1m. high) and shape • All sponges are sessile filter feeders Phylum Porifera

  4. Sponge Diversity Erect Rope Sponge Black-ball sponge Yellow Tube Sponge Phylum Porifera

  5. Porifera Anatomy • Thin, flat cells, called pinacocytes, line the outer surface of a sponge. • Some pinacocytes are specialized into tubelike, contractile porocytes, which regulate water circulation. • Below the pinacocyte layer is a jellylike layer called the mesohyl Phylum Porifera

  6. Porifera Anatomy • Mesenchyme cells move about in the mesohyl and can specialize to other functions including: • Reproduction • Secreting skeletal elements • Transporting and storing food • Forming contractile rings around openings in the sponge wall Phylum Porifera

  7. Choanocytes Collar Cells • Choanocytes: (collar cells) act as a pump to bring water into the sponge • Create water currents for filter feeding Phylum Porifera

  8. Sponge Support • Collagen is found between the inner canals and chambers • Mesohyl • Ameboid cells located in the mesohyl, have different roles • Archeocytes • Sclerocytes Phylum Porifera

  9. Sponge Support Phylum Porifera

  10. Spicules • Collagen is stiffened by adding microscopic mineral accretions or additional protein fibers (spongin) or both. • Spicules: skeleton structures, made of calcium carbonate (CaCO3) or silicon dioxide (SiO2). Spicules Phylum Porifera

  11. Sponge Types- Ascon Phylum Porifera

  12. Sponge Types- Sycon Phylum Porifera

  13. Sponge Types- Leucon Phylum Porifera

  14. Porifera Reproduction • Asexual budding • Regeneration: can regenerate from broken pieces • Gemmules- resistant capsules • Sexual • Usually hermaphroditic (monoecious) with male and female cells scattered throughout the connective tissue Phylum Porifera

  15. Porifera Larvae • Neighboring sponges are fertilized by sperm entering through the ostia • Ciliated mouth less larvae (parenchymella) is released. Parenchymella Phylum Porifera

  16. Sponge Life Cycle Phylum Porifera

  17. Porifera Classification • Phylum Porifera • Class Calcarea • Class Demospongiae • Class Hexactinellida • Sclerospongiae is no longer considered a class Phylum Porifera

  18. Class Calcarea • Have spicules made of calcium carbonate • Mostly small in size (<15 cm.), and form irregular masses • Never contain spongin, restricted to shallow water, and strictly marine Phylum Porifera

  19. Class Demospongiae (Most sponges) • Have spicules made of silicon dioxide (SiO2) or spongin or a combination of both • Most sponges belong to this class (90%) • Nearly all are leuconoid body type • Mostly found on the continental shelf • Spongia spp. (Bath sponge) Phylum Porifera

  20. Class Hexactinellida (Glass sponges) • Spicules are made of silica • Usually found in deep water on soft substrates in the tropics 200-1,000m. • Spicules are six pointed and have a lattice-like structure • Cup, vase or urn shape Euplectella (Deep sea Glass sponge) Phylum Porifera

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