منابع مشابه
john steinbeck: friend of the american common man
in his last years of life americans had almost forgotton steinbeck, and those who had not, occasionally criticized him for supporting and praising the u. s. military intervention in the vietnam war. althought ateinbeck incorporates different themes into his works, each one bears many signs of his concern and sympathy for america and the american common people in particular. steinbecks to a god ...
15 صفحه اولThe influence of water and light upon the pigmentary system in the common frog Rana temporaria.
Many factors, both internal and external, influence the chromatic changes of coldblooded vertebrates, and of these, three external variables are recognized as significant—light, heat and moisture. The frog can change its colour, from brown or black through intermediate tints to pale lemon, by changing the contraction and expansion of three types of chromatophores—the epidermal and dermal melano...
متن کاملGiants, Dwarfs and the Environment – Metamorphic Trait Plasticity in the Common Frog
In order to understand adaptation processes and population dynamics, it is central to know how environmental parameters influence performance of organisms within populations, including their phenotypes. The impact of single or few particular parameters in concert was often assessed in laboratory and mesocosm experiments. However, under natural conditions, with many biotic and abiotic factors po...
متن کامل[ 196] Glycogenolysis in the Liver of the Common Frog, Rana Temporaria
INTRODUCTION It has been known for many years that the metabolism of the frog is subject to seasonal variations. Liver glycogen and total body glycogen attain a maximum value in autumn, and a minimum in spring (Athanasiu, 1899; Pfluger, 1907; Kato, 1910; Bleibtreu, 1911; Goldfederowa, 1926). A few seasonal estimations of blood sugar were reported (Lesser, 1913; Slome, 1936), but the first compr...
متن کاملThe Effects of Alkali Metal Cations and Common Anions on the Frog Skin Potential
The effects on the potential difference across isolated frog skin (R. catesbeiana, R. pipiens) of changing the ionic composition of the bathing solutions have been examined. Estimates of mean values and precision are presented for the potential changes produced by substituting other alkali metal cations for Na at the outside border and for K at the inside border. In terms of ability to mimic Na...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Nature
سال: 1874
ISSN: 0028-0836,1476-4687
DOI: 10.1038/009305a0