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Medical Term:


Pronunciation: mi'kro-spor'a


A protozoan phylum, which includes the genera Nosema and Encephalitozoon, is characterized by the presence of unicellular spores with an imperforate wall and an extrusion apparatus having a polar tube and a polar cap; mitochondria are absent. They are intracellular parasites of invertebrates and lower vertebrates, with rare examples in higher vertebrates.

Synonym(s): Cnidospora

[micro- + G. sporos, seed]

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.