【摘 要】
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The morphology and ultrastructure ofBullacta exarata spermatozoa observed by light and transmission electronmicroscopy are presented in this paper. The spermato
【机 构】
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School of Life and Environmental Science,College of Life Sciences
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The morphology and ultrastructure ofBullacta exarata spermatozoa observed by light and transmission electronmicroscopy are presented in this paper. The spermatozoon is composed of head with a simple acrosomal complex and anelongated nucleus, and tail with a midpiece, principal piece and an end piece. The midpiece consists of a mitochondrial ring,and the principal piece is composed of axoneme and lateral fin. The structure orB. exarata spermatozoa differs significantlyfrom that of other gastropods, especially in the lateral fin and the principal piece, which was described scarcely before. Acomparison is made between B. exarata and other gastropods, and its significance on reproductive evolution andphysio-ecological adaptation is preliminarily discussed.
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