bi 212: lecture 6 phylum echinodermata. phylum echinodermata: spiny-skinned

Download Bi 212: Lecture 6 Phylum Echinodermata. Phylum Echinodermata: Spiny-skinned

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  • Slide 1
  • Bi 212: Lecture 6 Phylum Echinodermata
  • Slide 2
  • Phylum Echinodermata: Spiny-skinned
  • Slide 3
  • Evolutionary relationships and HOX genes Deuterostomes!
  • Slide 4
  • Echinodermata: 4 key features Calcareous internal skeleton Parts: Plates, spines and pedicellariae Why considered internal? Symmetry Bilateral symmetry (larvae) Pentamerous radial symmetry (adults) Water vascular system Derived from coelom Layout (next slide shows) Key function: tube foot control Other functions Mutable connective tissue What does this mean?
  • Slide 5
  • Body plan: Other aspects Perivisceral coelom Houses organs Gas exchange Hydrostatic skeleton Digestive system Can be highly branched Complete in some Nervous system No brain Branches parallel water vascular system Sensory (sea stars) Eye spots Receptors associated with tube feet No circulatory system No excretory system
  • Slide 6
  • Class Asteroidea: sea stars Feeding Stomach eversion Enzymes Respiration Tube foot ? ? Dermal papulae ? Protection Mechanisms?
  • Slide 7
  • Class Echinoidea: Sea urchins and others Feeding Aristotles lantern Main type of food? Respiration Tube foot ? ? Peristomial gills ? Protection Mechanisms?
  • Slide 8
  • Class Holothuroidea: Sea cucumbers Symmetry? Feeding Deposit feeders (what does this mean?) Respiration Respiratory tree ? Water entry into tree? Body surface ? Tube feet ? ? Protection Cuvarian tubules Evisceration
  • Slide 9
  • Class Ophiuroidea: Brittle stars, basket stars
  • Slide 10
  • Class Crinoidea Sea lilies