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Ferreira,Adelina; Kihara,Virginia Ojeda; Mehanna,Mahmoud. |
Reproductive strategy is the set of adaptations that promote the most efficient way that the species will survive under the particular conditions of a determined environment. Understanding these adaptations is important and can help pinpoint populations indicator of environmental changes. Spermatogenesis is a measurable biological process of these adaptations in spatial and temporal scales. We analyzed the morphology of the testes and oviducts of the lizard species that comprise the genus Tropidurus, taking into account the geographical distribution and sympatric relations. For the analysis and the testes were removed from the middle part of the oviducts from Tropidurus etheridge, T. oreadicus, T. itambere, T. spinulosus and T. Guarani species, collected... |
Tipo: Journal article |
Palavras-chave: Reproductive cycle; Lizards; Brazil. |
Ano: 2011 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022011000400058 |
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Cassel,Mônica; Mehanna,Mahmoud; Mateus,Lúcia; Ferreira,Adelina. |
The comprehension of the reproductive cycle allows to understand which are the morphological changes that develop in the gonad during this interval. Thus, many studies have been undertaken in order to describe and classify the stages of gonadal development and reproductive status of Neotropical fishes. For this purpose, specimens of Melanorivulusaff. punctatus were collected in a permanent dam in Chapada dos Guimarães, Mato Grosso, Brazil. The gonads were prepared for analysis by light microscopy. The oogenesis and spermatogenesis have been described, characterizing the stages of gonadal development, together with assessments of the gonadosomatic ratio, germ cell count and verification of variation of mature oocytes in females. Throughout the year the male... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Gonadossomatic ratio; Histology; Oogenesis; Spermatogenesis. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000100179 |
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Ferreira,Adelina; Dolder,Heidi. |
Spermatogenesis, with emphasis on spermiogenesis, is described for the lizard, Tropidurus itambere, using light microscopy, phase contrast and epifluorescence, as well as scanning and transmission electron microscopy. Cellular differentiation involves events of chromatin condensation, nuclear elongation and the formation of structural complexes, such as the acrosomal and axonemal ones. Other new characteristics, exclusive for this species, include various aspects of the subacrosomal granule, the insertion of the pro-acrosomal vesicle and the development of these structures to participate in the acrosomal complex. Radial projections occur just above the nuclear shoulders, which have been recognized already from the beginning of cellular elongation. The... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ultrastructure; Sperm; Spermatogenesis; Lizard; Tropiduridae. |
Ano: 2003 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452003000300006 |
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Ferreira,Adelina; Mehanna,Mahmoud; Prado,Cynthia P. A.. |
The spermatogenesis of Pseudis limellum, from the Southern Pantanal, Brazil, was studied from July 1995 to May 1996, through histological sections of the testis. The cells could be differentiated as: primary spermatogonia, large cells, generally with bilobed nucleus; secondary spermatogonia, smaller cells, with darker cytoplasm, chromatin of radial form; primary and secondary spermatocytes, differentiated according to the different stages of the nucleus during the successive cells divisions. Furthermore, we observed cells in process of morphologic differentiation: rounded spermatids much smaller, with nucleus containing chromatin in compacting process and cytoplasm reduction; elongated spermatids, generally parallel organized in well defined bundles, with... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Spermatogenesis; Male; Amphibia; Climatic influences. |
Ano: 2008 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452008000200004 |
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Miranda,Núbia Esther de Oliveira; Ferreira,Adelina. |
A morfologia bucal interna das larvas de Eupemphix nattereri, Physalaemus albonotatus, P. centralis, P. cuvieri, Leptodactylus furnarius, L. fuscus, L. petersii e L. podicipinus são descritas e comparadas utilizando microscopia eletrônica de varredura. A larva de E. nattereri apresenta muitas diferenças quando comparada à larvas de anuros do gênero Physalaemus. As larvas de P. albonotatus, P. centralis e P. cuvieri apresentam semelhanças em sua morfologia bucal interna, tais como o número de papilas infralabiais e papilas laterais à crista mediana. P. centralis difere na quantidade de papilas pós-nasais e papilas da arena do teto bucal. Entre as larvas de Leptodactylus é possível perceber um padrão na distribuição e quantidade das estruturas bucais... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Anatomia bucal interna; Descrição; Girinos; Leiuperidae; Leptodactylidae. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032009000200016 |
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