Abstract
1. In the heads of maturing sperm of a locust the chromatin becomes arranged in a highly regular manner so as to produce many parallel lines about 60 A thick in longitudinal section and contiguous polygons in transverse section. 2. This configuration appears after fixation in osmium tetroxide, formaldehyde, or acetic acid; intermediate stages in its development are illustrated. 3. These electron micrographs are interpreted to mean that, during sperm maturation, the chromatin becomes formed into sheets and then into tubes running parallel with the long axis. 4. In the mature sperm head we have been unable so far to detect this structure. This may be because the chromatin becomes so compact during the shrinkage of the nucleus which occurs during formation of the mature sperm.
Full Text
The Full Text of this article is available as a PDF (830.2 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- BRADFIELD J. R., GIBBONS I. R. The fixation of cell nuclei by osmium tetroxide. Biochim Biophys Acta. 1956 Dec;22(3):506–513. doi: 10.1016/0006-3002(56)90061-0. [DOI] [PubMed] [Google Scholar]
- BURGOS M. H., FAWCETT D. W. An electron microscope study of spermatid differentiation in the toad, Bufo arenarum Hensel. J Biophys Biochem Cytol. 1956 May 25;2(3):223–240. doi: 10.1083/jcb.2.3.223. [DOI] [PMC free article] [PubMed] [Google Scholar]
- GRASSE P. P., CARASSO N., FAVARD P. L'ultrastructure des chromosomes et son évolution au cours de la spermiogenèse d'Helix pomatia. II. Le spermatozoïde. C R Hebd Seances Acad Sci. 1956 Mar 12;242(11):1395–1398. [PubMed] [Google Scholar]
- GRASSE P. P., CARASSO N., FAVARD P. L'ultrastructure des chromosomes et son évolution au cours de la spermiogenèse de l'Escargot Helix pomatia. I. La spermatide; nouvelle conception de la structure des chromosomes. C R Hebd Seances Acad Sci. 1956 Feb 20;242(8):971–975. [PubMed] [Google Scholar]
- KELLENBERGER E., TURIAN G. Ultrastructure du corps paranucléaire, des mitochondries et de la membrane nucléaire des gamètes d'Allomyces macrogynus. Exp Cell Res. 1956 Aug;11(2):417–422. doi: 10.1016/0014-4827(56)90117-3. [DOI] [PubMed] [Google Scholar]
- MOSES M. J. Chromosomal structures in crayfish spermatocytes. J Biophys Biochem Cytol. 1956 Mar 25;2(2):215–218. doi: 10.1083/jcb.2.2.215. [DOI] [PMC free article] [PubMed] [Google Scholar]
- RUDZINSKA M. A., PORTER K. R. Observations on the fine structure of the macronucleus of Tokophrya infusionum. J Biophys Biochem Cytol. 1955 Sep 25;1(5):421–428. doi: 10.1083/jcb.1.5.421. [DOI] [PMC free article] [PubMed] [Google Scholar]