✦ LIBER ✦

The fine structure of the spermatozoon of Pennaria tiarella (coelenterata)

✍ Scribed by Robert G. Summers

Publisher: John Wiley and Sons
Year: 1970
Tongue: English
Weight: 890 KB
Volume: 131
Category: Article
ISSN: 0362-2525
DOI: 10.1002/jmor.1051310108

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

Spermatozoa of the hydroid Pennaria tiarella were examined with the electron microscope. The anterior region is characterized by the presence of 30–40 membrane‐bounded vesicles which lie anterior to the nucleus. These vesicles are apparently derived from the Golgi apparatus.

The nucleus is conical in shape with a protrusion at the anterior end. Posteriorly it is indented by four radially arranged mitochondria. Lying within the fossa formed by the mitochondria are proximal and distal (filament forming) centrioles. The distal centriole is characterized by nine centriole satellite projections which emanate from its matrix. The tubules of the distal centriole are continuous with the alpha filaments of the tail.

The tails are typical 9 + 2 flagella with 9 peripheral doublet (or alpha) filaments surrounding two central (or beta) filaments.

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