Data/hora: 08/06/2024 12:31:25

Provedor de dados: | Zoologia
País: | Brazil
Título: | Histological characterization of cellular types during Scinax fuscovarius oogenesis (Lutz) (Anura, Hylidae)
Autores: | Oliveira,Classius de; Santos,Lia Raquel de Souza.
Data: | 2004-12-01
Ano: | 2004
Palavras-chave: | Oocytes; Oogonia; Ovary; Pigment; Vitellogenesis.
Resumo: | This paper describes morphological characteristics of the ovarian germinative cells of the Scinax fuscovarius (Lutz, 1925). The ovary is organized in primordial germinative cells (oogonia) and follicular structures (ovarian follicle) - oocytes surrounded by follicular cells. Oogonia: their nests are peripherically localized, containing cells with large and oval nucleus. Oocytes I: basophilic cytoplasm; the spherical nucleus presents few nucleoli, one or two; the follicular cells (one tenuous layer) surround these previtellogenic cells. Oocytes II: the cell is larger and the cytoplasm becomes more basophilic; the nucleus presents few nucleoli and contains many chromosomes in the periphery (beginning the perinucleolar stage). Oocytes III: the cytoplasm acquires an intense acidophilia; the peripherical region of cytoplasm is filled with yolk and the internal region has no yolk at all; pigment synthesis begins; the follicular envelope presents three tenuous layers: an inner acellular (vitelline envelope) and two cellular layers (follicle cells). Oocytes IV: a characteristic of this stage is the differentiation between the animal and the vegetal poles; the nucleus in the animal hemisphere and the pigments give the oocyte a color dark brown; the vitellogenesis is intense and the yolk occupies the whole cytoplasm.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752004000400029
Editor: | Sociedade Brasileira de Zoologia
Relação: | 10.1590/S0101-81752004000400029
Formato: | text/html
Fonte: | Revista Brasileira de Zoologia  v.21 n.4 2004
Fonte: | info:eu-repo/semantics/openAccess