Aeb201 porifera sponge

• Porifera may be regarded as a branch outside the line of evolution from Protozoan to other Metazoa and are called Parazoa
• Level of organization in Porifera

  Cellular compared to Eumetazoa which is at tissue level, no organs or tissues
• Porifera is the only phylum that will be dealt with in detail
• Choanocyte

  Cell component lining the spongocoel
• Sponges can be regarded as loose aggregations of cells for most physiological purposes
• Porifera belong to the cellular level of organization and are more complex than Metazoa and Placozoa
• Lowest Metazoan phyla


  • Metazoa
  • Placozoa
  • Porifera
• Porifera belongs to the Parazoa branch of Metazoa


  Although multicellular, they do not fit into the general plan of other phyla
• Porifera differs from other Metazoa in their cellular layers and patterns of development
• Poriferans are considered aberrant and deviate widely from standard patterns
• Sponges have developed a unique system of water current for food and oxygen
• Classification of Porifera

  • Class Calcarea
  • Class...
• General characteristics of Porifera

  • Form and size
  • Symmetry
  • Germ layers
  • Organs and tissues
  • Mode of living
  • Locomotion
  • Body covering and skeleton
  • Nutrition
  • Nervous system
  • Excretion
  • Transport system
  • Habitat
  • Reproduction
• Sponges provide shelter and habitat for a variety of small organisms
• Sponges absorb oxygen from the water flowing through their bodies and release carbon dioxide for gas exchange
• Sponges expel waste products back into the surrounding water
• Poriferans have a unique body structure and perform various functions within their ecosystem
• Poriferans actively pump water through their bodies to capture and ingest small particles
• Poriferans


  Simple multicellular organisms belonging to the phylum Porifera
• Functions of poriferans

  • Filter Feeding
  • Oxygen Exchange
  • Waste Removal
  • Habitat
  • Chemical Defense
• Form of poriferans

  • Body Structure
  • Canal System
  • Spicules
  • Body Shape
• Poriferans are commonly known as sponges
• Poriferans belong to the phylum Porifera
• Some sponges have hard, needle-like structures called spicules embedded in their body for support and protection
• Many ostia or tiny pores in the body wall facilitate the incoming flow of water
• Sponges possess a central cavity (spongocoel) which opens to the outside through the osculum for water outlet
• The three layers of the body wall sponges are Pinacoderm, Mesohyl, and Choanoderm
• The opening are connected by a specialized canal system, lined with flagellated choanocytes for phagocytic absorption of food
• Types of cells found in poriferans

  • Pinacocytes
  • Choanocytes
  • Archaeocytes
  • Sclerocytes
  • Spongocytes
  • Collencytes
  • Lophocytes
• The canal system can be classified into three types: Asconoid system (flagellate spongocoels), Synconoid system (flagellate canal), Leuconoid system (flagellate chambers)
• Reproduction in Poriferans

  1. Sexual reproduction through release of gametes into water

  2. Asexual reproduction through budding or fragmentation
• Poriferans

  • Filter water
  • Provide habitat for other organisms
  • Contribute to nutrient cycling
• Types of Skeleton in Poriferans

  • Siliceous Spicules
  • Calcareous Spicules
  • Spongin Fibers
• Calcareous Spicules


  • Serve as a skeletal framework for the sponge's body
• Siliceous Spicules

  • Provide structural support and protection
  • Can be simple or complex in shape
• Poriferans play important ecological roles in marine ecosystems
• Spongin Fibers


  • Composed of flexible, protein-based fibers
  • Give the sponge flexibility and strength
• Physiology of Sponges

  1. Feeding

  2. Digestion

  3. Respiration

  4. Excretion

  5. Reproduction

  6. Regeneration
• Sponges are filter feeders that actively pump water through their bodies to capture food particles
• Choanocytes

  • Have a distinctive collar-like structure surrounding a flagellum
  • Create water currents to bring in food particles and oxygen
  • Capture and digest food particles through phagocytosis