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Full-Text Articles in Cell Anatomy
The Tadpole Of Proceratophrys Avelinoi (Anura: Leptodactylidae), Rafael O. De Sá, José A. Langone
The Tadpole Of Proceratophrys Avelinoi (Anura: Leptodactylidae), Rafael O. De Sá, José A. Langone
Biology Faculty Publications
The genus Proceratoprhrys is poorly known. It consists of 14 currently recognized species (Frost, 2000) of medium-sized frogs distributed from northeastern Argentina and Paraguay to southeast Amazonia (Rondonia State), eastern and southern Brazil. Proceratophrys avelinoi was described from Misiones, Argentina (Mercadal de Barrio and Barrio, 1993). The larval stage of this species is unknown. Herein, we describe the tadpole and the characteristics of the internal oral anatomy of P avelinoi using scanning electron micros- copy (SEM).
The Timing And Pattern Of Myogenesis In Hymenochirus Boettgeri, Matthew T. Smetanick, Rafael O. De Sá
The Timing And Pattern Of Myogenesis In Hymenochirus Boettgeri, Matthew T. Smetanick, Rafael O. De Sá
Biology Faculty Publications
Differences in the relative timing of homologous developmental events among closely related species, known as heterochronies, may provide valuable clues in understanding evolutionary relationships (McKinney, 1988; McNamara, 1995). Examining the timing of myogenic events is a relatively easy and effective method for finding heterochronic events. For example, whether muscle proteins and myofibrils appear before or after multinucleation can be determined through histological techniques (Kielbowna, 1981). Simple observations of live specimens can pinpoint functional landmarks such as first twitch (spontaneous or due to external stimuli) and first heartbeat.
Organization And Polarity Of Protoplasm, John P. Munson
Organization And Polarity Of Protoplasm, John P. Munson
All Faculty Scholarship for the College of the Sciences
In higher forms of life, we usually concede the presence of an organ specialized for the performance of a function. In these higher forms coordination of organs, which entails a regular sequence in their functions, is readily made out; and it seems a mere platitude to say, of these, that organization determines the functions of the organism. To what extent can functions exist in the absence of organization; does the one precede the other; or have function and organization developed simultaneously, out of matter devoid of both structure and function? In my studies on the cell, I have kept these …