Search results
Results from the WOW.Com Content Network
The common frog is a poikilotherm and is able to function over a wide range of body core temperatures. A poikilotherm (/ ˈ p ɔɪ k ə l ə ˌ θ ɜːr m, p ɔɪ ˈ k ɪ l ə ˌ θ ɜːr m /) is an animal (Greek poikilos – 'various', 'spotted', and therme – 'heat') whose internal temperature varies considerably.
The mesonephros persists and forms the anterior portion of the permanent kidneys in fish and amphibians, but in reptiles, birds, and mammals, it atrophies and for the most part disappears rapidly as the permanent kidney (metanephros) begins to develop [2] during the sixth or seventh week. By the beginning of the fifth month of human development ...
The development of the kidney proceeds through a series of successive phases, each marked by the development of a more advanced kidney: the archinephros, pronephros, mesonephros, and metanephros. [1] The pronephros is the most immature form of kidney, while the metanephros is most developed. The metanephros persists as the definitive adult kidney.
The world's largest frog is the goliath frog of West Africa—it can grow to 15 inches (38 centimeters) and weigh up to 7 pounds (3.2 kilograms). One of the smallest is the Cuban tree toad, which ...
Frogs are valued as food by humans and also have many cultural roles in literature, symbolism and religion. They are also seen as environmental bellwethers, with declines in frog populations often viewed as early warning signs of environmental damage. Frog populations have declined significantly since the 1950s.
He began testing the frog secretions to determine whether or not the peptides would have an effect on bacteria that attack human cells. He found the chemical ranatuerin-2CSa, which is produced by R. cascadae, impeded the growth of E. coli and S. aureus in humans. These anti-infective agents give the Cascades frogs "therapeutic potential for the ...
Scientists have grown kidneys containing mostly human cells inside pig embryos, an important step toward growing kidneys and potentially other human organs.
Pronephros is the most basic of the three excretory organs that develop in vertebrates, corresponding to the first stage of kidney development. It is succeeded by the mesonephros, which in fish and amphibians remains as the adult kidney. In amniotes, the mesonephros is the embryonic kidney and a more complex metanephros acts as the adult kidney ...