septate junction

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septate junction A type of adhesive cell junction, particularly characteristic of invertebrate tissues, in which the membranes forming the junction are held very regularly 15–17 nm apart. Traversing this gap at right angles to the cell surface there are crossbars of dense material, the septa. In sections taken parallel to the cell surface, these septa are revealed as pleated sheets that zigzag between the opposed membranes in parallel rows.