The sugar oxidation cascade: aerial refueling in hummingbirds and nectar bats
نویسندگان
چکیده
منابع مشابه
The sugar oxidation cascade: aerial refueling in hummingbirds and nectar bats.
Most hummingbirds and some species of nectar bats hover while feeding on floral nectar. While doing so, they achieve some of the highest mass-specific V(O(2)) values among vertebrates. This is made possible by enhanced functional capacities of various elements of the 'O(2) transport cascade', the pathway of O(2) from the external environment to muscle mitochondria. Fasted hummingbirds and necta...
متن کاملSugar Metabolism in Hummingbirds and Nectar Bats
Hummingbirds and nectar bats coevolved with the plants they visit to feed on floral nectars rich in sugars. The extremely high metabolic costs imposed by small size and hovering flight in combination with reliance upon sugars as their main source of dietary calories resulted in convergent evolution of a suite of structural and functional traits. These allow high rates of aerobic energy metaboli...
متن کاملIntestinal paracellular absorption is necessary to support the sugar oxidation cascade in nectarivorous bats.
We made the first measurements of the capacity for paracellular nutrient absorption in intact nectarivorous bats. Leptonycteris yerbabuenae (20 g mass) were injected with or fed inert carbohydrate probes L-rhamnose and D(+)-cellobiose, which are absorbed exclusively by the paracellular route, and 3-O-methyl-D-glucose (3OMD-glucose), which is absorbed both paracellularly and transcellularly. Usi...
متن کاملStoking the Brightest Fires of Life Among Vertebrates
Hummingbirds and nectarivorous bats in flight display some of the highest rates of aerobic metabolism among vertebrates. Analysis of the pathway of oxygen, i.e., the “oxygen transport cascade”, reveals the concerted upregulation of capacities for O2 flux from the external environment, through the respiratory and cardiovascular systems, into muscle mitochondria. Pathways for aerobic energy metab...
متن کاملThe Metabolic Flexibility of Hovering Vertebrate Nectarivores.
Foraging hummingbirds and nectar bats oxidize both glucose and fructose from nectar at exceptionally high rates. Rapid sugar flux is made possible by adaptations to digestive, cardiovascular, and metabolic physiology affecting shared and distinct pathways for the processing of each sugar. Still, how these animals partition and regulate the metabolism of each sugar and whether this occurs differ...
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: Journal of Experimental Biology
سال: 2011
ISSN: 1477-9145,0022-0949
DOI: 10.1242/jeb.047936