Ultrastructure of synapses in the first-evolved nervous systems

  title={Ultrastructure of synapses in the first-evolved nervous systems},
  author={Jane A. Westfall},
  journal={Journal of Neurocytology},
SummaryThe phylum Cnidaria represents the first group of animals to evolve a recognizable nervous system. A comparison of the ultrastructural features of synaptic loci in animals representing all four classes of the cnidaria has provided an overview of the first-evolved synapses that can be compared morphologically to synapses in higher forms. Synapses in these watery jellylike animals with unmyelinated axons are sparse and difficult to fix well. However, we now have sufficient evidence to… 

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  • P. Pierobon
  • Biology
    The International journal of developmental biology
  • 2012
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Do jellyfish have central nervous systems?

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Synapses provide pathways of communication between cells throughout the animal kingdom wherever a nervous system is present. The most primitive or elementary nervous system that can be readily

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