Bidart Campos, German J. – Manual De La Constitución Reformada – Tomo II. La constitución comentada y concordada — TOMO II – M A. Gelli – MB. .. UNIDAD II. Manual-de-la-Constitucion-Reformada. Bidart-Campos. .. Badeni- UNIDAD II.
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Skip to main content. Log In Sign Up. Universidad Nacional del Nordeste Corrientes, Argentina. All Departments 28 Documents Researchers. Acd acordada de tasas. Ley de responsabilidad estatal Embryonic development of Columba livia Aves: Columbiformes from an altricial-precocial perspective. The ontogeny of this species was divided into lq phases: The middle phase stages was characterized mainly by the growth of limbs and the organization of the autopodium, the formation and growth of the peak, and the development of integumentary annexes such as feather germs and leg scales.
The late phase stages shows the overall embryo growth, the final organization of the pterilosis pattern and growth of feather germs, as well manaul final consumption of the yolk, and hatching.
Therefore we propose some hypotheses about possible heterochronic events related to altricial-precocial developmental models. La ontogenia de dicha especie fue rsformada en tres etapas: Reproductive aspects of Dendropsophus sanborni Anura, Hylidae in northeastern Argentina.
The aim of this investigation was to characterize reproductive aspects of Dendropsophus sanborni Schmidt, Anura, Hylidae in the northwest The aim of this investigation was to characterize reproductive aspects biadrt Dendropsophus sanborni Schmidt, Anura, Hylidae in the northwest of Corrientes province, in northeastern Argentina.
The reproductive cycles of males and females, the existence of sexual dimorphism and the male’s vocalization period were analyzed. Samplings were made from September to August Dendropsophus sanborni showed a prolonged reproductive pattern because mankal activity was observed during most part of the year. Calling males were recorded all months except in July.
The spermatogenic cycle can be characterized as potentially continuous. In males, snout-vent length was significantly correlated with mean testicular volume.
The species showed sexual dimorphism in body mass, with females larger than males. Post-ovulatory females were found from March to June and most females had oocytes at different stages of maturity, with abundant post-vitellogenic oocytes from August to December.
Aspectos reproductivos de Dendropsophus sanborni Anura, Hylidae en el nordeste de la Argentina.
Germán J. Bidart Campos (Author of Compendio de Derecho Constitucional)
Los muestreos se efectuaron desde Septiembre de hasta Agosto de In the birds, the gonads are organized and differentiate to dividing a couple of genital combs, which are constituted by Cells Germinate Primordial CGPsof origin extra-gonadal.
Studies of the development gonadal in birds have been studied in species model as Gallus gallus domesticus. From these two models, the study of the development gonadal in different species of birds will help to elucidate variations in the patterns of development gonadal in vertebrates. We analyzed the histological constitution of testicles of embryos from the stage E.
And neonatos of 4, 13 and 25 days post-hatching dpe. The histological analysis showed that from E. During ovarian ontogeny of birds can recognize five key events: Th e knowledge of these events is crucial for the interpretation of the processes involved in the diff erentiation of female gametes. Th is paper describes the changes and cellular events involved in the formation of the follicles of Columba livia.
To do this, we examined the histology ovarian from stage embryos E42 and neonates, 2, 5, 7, 10 and 14 days post hatch. Samples were processed according to conventional techniques for paraffi n embedding and staining with hematoxylin and eosin. Th e observations made it possible to identify four stages of folliculogenesis. In stage I the oogonia nests are grouped surrounded by a layer of pre follicular cells. Stage II is characterized by the initiation and meiotic arrest of prophase and primary oocytes.
From stage III starts follicular cells surrounding each oocyte culminating in the organization of primordial follicles stage IV.
Th e results obtained show that in Columba livia, unlike the other species studied, folliculogenesis begins after hatching, and raising new questions about the mechanisms of control of folliculogenesis. Future studies will focus on the analysis of diff erentiation processes of follicular cells and endocrine control in the process.
Bolilla 3 Actos de Gobierno Politicos e Institucionales. Las demostraciones y los desarrollos, son descritos de manera suficiente, pero sin cansar demasiado al estudiante.
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Los argumentos intuitivos e informales conservan una claridad apropiada. Bidart Campos, German J.
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