Naked axons and symmetrical synapses in coelenterates
Date
1962-12-01
Authors
Horridge, George Adrian
Mackay, Bruce
Journal Title
Journal ISSN
Volume Title
Publisher
Company of Biologists Ltd
Abstract
Summary
Examination of sections of the marginal ganglion of the jellyfish Cyanea and the hydromedusan Phialidium by the electron microscope, in a region where nervous tissue is readily identified on account of its abundance, reveals the following features.
Nerve-cell bodies and axons are crowded together without special glial cells. The axons form a layer between the cell-bodies and the mesogloea and the spaces between them are continuous with other intercellular spaces and with the mesogloea.
Features typical of nerve-cells in other animals are mitochondria, Golgi region (= γ-cytomembranes), neurotubules (= canaliculi) about 16 mµ wide, and several types of vesicle ranging in size from 50 to 200 mµ, including synaptic vesicles of 50 to 100 mµ.
Features not typical of nerve-cells are the modified (possibly sensory) cilia on the dendrites of bipolar cells and the absence of clumps of Nissl substance and neurofilaments.
Synapses between axons (or with a perikaryon) have a synaptic cleft of 18 to 22 mµ and a crowded row of synaptic vesicles within the neurones on each side of the synapse.
Description
Keywords
jellyfish, Cyanea, hydromedusan, Phialidium, axon, coelenterate, ganglion
Citation
Collections
Source
The Quarterly journal of microscopical science
Type
Journal article
Book Title
Entity type
Access Statement
Open access via publisher website
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DOI
Restricted until
2037-12-31