Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl

Refine search results

Journals help

  1. 2 Folia Biologica

Years help

  1. 1 2009

  2. 1 2003

Authors help

  1. 2 Pecio A.

Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 2

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1

Ultrastructural examination of spermiogenesis and spermatozoon ultrastructure in Congo tetra Phenacogrammus interruptus Boulenger, 1899 (Ostariophysi: Characiforme

100%
Pecio A.
Folia Biologica
|
2009
|
vol. 57
|
issue 1-2
13-21
EN
Ultrastructural studies of spermiogenesis in Phenacogrammus interruptus using transmission electron microscopy revealed that the process is characterized by flagellum development, formation of a cytoplasmic canal, nuclear rotation, and nuclear fossa formation. Chromatin compaction proceeds during spermatid transformation within the spermatocysts as well as after spermiation within the lumen of the efferent ducts. The spermatozoon is of primitive type and exhibits characters typical for Type I aquasperm. The head consists of a spherical nucleus with highly condensed chromatin and a centrally located electron lucent area connected to a moderate-sized nuclear fossa. The nuclear fossa contain centrioles in perpendicular arrangement, surrounded by osmiophilic fibrous material. In the short midpiece, several mitochondria and vesicles are unevenly distributed in the cytoplasm forming the cytoplasmic collar at the base of the nucleus. The cytoplasmic collar surrounds the initial part of the flagellum, running in the cytoplasmic canal. The flagellar axoneme has a typical pattern (9x2+2) and the flagellum contains membranous compartments in the portion immediately posterior to the termination of the cytoplasmic canal.
2

Spermiogenesis and the fine structure of the spermatozoon in a Headstander, Chilodus punctatus (Teleostei, Characiformes, Anostomidae)

100%
Pecio A.
Folia Biologica
|
2003
|
vol. 51
|
issue 1-2
55-62
EN
The main characteristic features of spermiogenesis in Chilodus punctatus (Characiformes) are rotation of the nucleus, development of a nuclear fossa, which extends as a narrow invagination deep into the nucleus and the way in which flagellum is formed. The chromatin condensation proceeds during the spermiogenesis from heterogeneous through homogenous and granular to a highly compact one present in the mature spermatozoon. Mature Ch. punctatus spermatozoon shows a spherical nucleus, short midpiece and flagellum with lateral fins. The centrioles are in perpendicular arrangement and are located in the deep nuclear fossa, which extends towards the anterior pole of the nucleus. The midpiece contains a few mitochondria, which are separated from the anterior fragment of flagellum by the cytoplasmic channel. Spermiogenesis and spermatozoon ultrastructure conform to the pattern observed in other ostariophysans, but for the first time the presence of lateral fins along flagellum has been documented in a representative of Characiformes.
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.