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Porifera and Cnideria exam Flashcards

Porifera and Cnideria exam
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  • Porifera
    A phylum of hermaphroditic filter feeders, commonly known as sponges, that reproduce both sexually and asexually.
  • Cnidaria
    A phylum that includes jellyfish, characterized by a radial body plan and a gastrovascular cavity for nutrient absorption.
  • Spongocoel
    The central cavity in sponges, lined with choanocytes for feeding through phagocytosis.
  • What are choanocytes?
    Flagellated cells in sponges that capture food particles and bacteria for feeding through phagocytosis.
  • Cnidocytes
    Specialized stinging cells in cnidarians that contain nematocysts for capturing prey.
  • What is the function of nematocysts?
    To shoot out a penetrating barb that stings and immobilizes prey, allowing cnidarians to capture and eat it.
  • Polyp
    One of the two body forms of cnidarians, characterized by a cylindrical body and tentacles, often attached to a surface.
  • Medusa
    The free-swimming, bell-shaped body form of cnidarians, with tentacles hanging down.
  • What is the mesohyl?
    A gelatinous matrix within sponges that separates different regions of the sponge body and contains amoebocytes.
  • Amoebocytes
    Cells in sponges that create structural fibers and transport nutrients.
  • Gastrovascular cavity
    A central cavity in cnidarians responsible for digestion and nutrient distribution.
  • What is a hydrostatic skeleton?
    A structure in cnidarians where fluid pressure within the body cavity provides support and shape.
  • Hermaphroditic
    An organism that has both male and female reproductive organs.
  • What are Anthozoa?
    A class of cnidarians that includes corals and sea anemones, often with calcium carbonate exoskeletons.
  • Filter feeders
    Organisms that feed by straining suspended matter and food particles from water.
  • What is the osculum?
    The opening in a sponge through which water exits after passing through the spongocoel.
  • Radial symmetry
    A body plan in which any longitudinal cut through the organism's central axis results in identical halves.
  • Intracellular digestion
    The process by which food is digested within the cells, as seen in sponges.
  • What is the primary function of the gastrovascular cavity in cnidarians?
    To digest food and distribute nutrients throughout the organism.
  • Calcium carbonate exoskeleton
    A hard, external structure made of calcium carbonate, found in some cnidarians like corals.
  • What is phagocytosis?
    The process by which cells engulf and digest particles, used by choanocytes in sponges.
  • Sessile
    Describes an organism that is fixed in one place and does not move, although some polyps can detach to escape predators.
  • What is the main difference between polyps and medusae?
    Polyps are usually attached to a surface with tentacles facing upward, while medusae are free-swimming with tentacles hanging down.
  • Cnidarian
    An animal belonging to the phylum Cnidaria, which includes jellyfish, corals, and sea anemones.
  • What is the role of flagella in choanocytes?
    To create water currents and capture food particles for feeding.
  • Exoskeleton
    A rigid external covering that provides support and protection, found in some cnidarians like corals.
  • What is the significance of the radial body plan in cnidarians?
    It allows the organism to interact with the environment from all directions, aiding in feeding and defense.
  • Phylum
    A taxonomic rank in the biological classification system, grouping together organisms with similar characteristics.