Posts tagged metabolism
Sonic hedgehog is one of three proteins in the mammalian signaling pathway family called hedgehog, the others being desert hedgehog (DHH) and Indian hedgehog (IHH). SHH is the best studied ligand of the hedgehog signaling pathway. It plays a key role in regulating vertebrate organogenesis, such as in the growth of digits on limbs and organization of the brain. Sonic hedgehog is the best established example of a morphogen as defined by Lewis Wolpert’s French flag model—a molecule that diffuses to form a concentration gradient and has different effects on the cells of the developing embryo depending on its concentration.
A million ruby-throated hummingbirds will consume much more food than one African Elephant, even though both have about the same biomass (3,000kg, or 3.3 US tons). Thus, ants, as a group, may actually consume more resources per year than antarctic krill, even though both may have roughly the same biomass, because ants tend to be smaller, and live in warmer environments. Although there may be about 10-15 times the biomass of termites than cows in the world, studies have suggested that termites might produce almost 30,000 times as much methane per year because of their faster metabolism.
University of Southern California (USC) have discovered bacteria that survives on nothing but electricity — rather than food, they eat and excrete pure electrons. These bacteria yet again prove the almost miraculous tenacity of life — but, from a technology standpoint, they might also prove to be useful in enabling the creation of self-powered nanoscale devices that clean up pollution. Some of these bacteria also have the curious ability to form into ‘biocables,’ microbial nanowires that are centimeters long and conduct electricity as well as copper wires — a capability that might one day be tapped to build long, self-assembling subsurface networks for human use.
Polyethylene (PE) has been considered nonbiodegradable for decades. Although the biodegradation of PE by bacterial cultures has been occasionally described, valid evidence of PE biodegradation has remained limited in the literature. We found that waxworms, or Indian mealmoths (the larvae of Plodia interpunctella), were capable of chewing and eating PE films.