PHYLUM

• Phylum Porifera - porus = pore + fer = bearing; most primitive animal phylum; simple body plan with pores and water channel
• Phylum Porifera

  • example = sponge
• Phylum Porifera

  • Straining or Filtering - feeding system of sponges in getting food particles from water
  • Filter feeders
• Phylum Porifera

  • Collar cells - filters and strains food from water; help to get water flow through the sponge
• Phylum Porifera

  • Osculum - aperture or hole through which water is expelled
• Phylum Porifera can reproduce both sexually and asexually

  • Sexually - Synchronous Spawning
  • Asexually - Budding
• Phylum Cnidaria - cnidos = stinging; invertebrates; has two true tissue layers; gastrovascular cavity, no anus but with mouth
• Phylum Cnidaria

  • Has no Mesoderm tissue layer
• Phylum Cnidaria can be in the form of Medusa or Polyp

  • Medusa - mobile life stage of cnidaria; with movement
  • Polyp - sessile life stage or immobile; fixed and attached; no movement
• Phylum Cnidaria

  • Cnidocytes - stinging cells which contains organelles called nematocysts = stingers for capturing prey
• Phylum Cnidaria

  • example/s - jellyfish, sea anemones
• Phylum Ctenophora - kteis/kten = comb + pherein = to bear; contains cylia for movement; has no nematocysts or stingers
• Phylum Ctenophora

  • Sexual Reproduction: Hermaphroditic; releases sex cells in the water; external fertilization
• Phylum Platyhelminthes - platy = flat + helminth = worm; bilateral symmetry; triploblastic or contains three true tissue layers
• Three True Tissue Layers

  • Ectoderm - forms the exoskeleton
  • Mesoderm - develops into organs
  • Endoderm - forms the inner lining of the organs
• Phylum Ctenophora

  • example/s: comb jelly
• Flame cells - excretory cell that function like a kidney; removes waste materials through filtration
• Phylum Platyhelminthes

  • no digestive tract, hermaphroditic
  • parasitic form - needs a host
• Why do parasites need a host?

  To absorb nutrients
• Phylum Platyhelminthes Parts

  • Rostellum - attaches to host
  • Sucker - absorbs nutrients
• Phylum Platyhelminthes are segmented

  • Proglottid - segments of tapeworms which contains structures such as reproductive system that is detachable
• Phylum Platyhelminthes

  • Gravid Proglottid - filled with eggs
  • Mature Proglottid, Immature Proglottid
• Phylum Platyhelminthes

  • example/s: flatworms, tapeworms
• Bilateral Symmetry - the left and right side of an organism mirror each other or extremely identical
• Phylum Annelida - anellus = ring; bilaterally symmetrical; complete digestive tract; breathe through their skin; has proglottids and uses its segments for movement
• Phylum Annelida

  • example/s: earthworms
• Phylum Annelida Parts

  • Parapodia - lateral extensions supported by chitin (polysaccharide exoskeleton of crustaceans)
• Phylum Annelida Parts

  • Chitinous setae - bristles secreted; important for locomotion and digging; this makes it difficult to pull a worm straight from the ground
• Phylum Annelida Parts

  • Clitellum - non-segmented section which protect the offspring of earthworms
• Phylum Nematoda - nema/nematos = thread + odes = of the nature of; free-living and parasitic; triploblastic
• Phylum Nematoda

  • example/s: round worms
• Phylum Nematoda

  • Chitinous cuticle - extra protective layer; non-living cuticle secreted by epidermis
• Phylum Nemertea - Nemertes = name of a sea nymph; bilaterally symmetrical; well developed brain; has mouth and anus; has blood system
• Phylum Nemertea

  • example/s - ribbon worms
• Phylum Nemertea

  • Fertilization takes place - externally
• Phylum Nemertea Parts

  • Proboscis - muscular structure (detaches) which attacks and captures their prey
• Phylum Nemertea Parts

  • Sensory papillae - sense or feels before proboscis is secreted to attack
• Phylum Rotifera - rotifer = wheel-bearer; body has no cilia except for its ciliated crown; complete digestive tract; dioecious-parthenogenetic
• Phylum Rotifera

  • example/s - rotifers
• Phylum Rotifera Parts

  • Gonad - organ that produce sex cells