Word: amino
(lookup in dictionary)
(lookup stats)
Dates: during 1970-1979
Sort By: most recent first
(reverse)
...ammonia and methane, the first forerunners of life emerged. How those complex molecules were formed remains a profound mystery. But scientists believe that some of the earth's primordial atmospheric molecules were broken up into their constituent atoms; regrouping into new molecules, these atoms formed organic compounds called amino acids, which are the building blocks of protein-and of life...
...concatenation has long been the subject of lively scientific debate. Was the crucial reaction powered by intense ultraviolet radiation from the sun? By bolts of lightning in the primeval skies? Or by the searing heat of volcanic eruptions on the surface of the young planet? Researchers have found that amino acids can be produced in laboratory simulations of each of those conditions. Now a team of investigators at Cornell University has proposed that another natural phenomenon might have played a role. The catalyst of genesis, they say, could have been the shock waves of thunderclaps or even of meteors plunging...
...other end of the tube, which contained chemically inert helium. The Bar-Nuns increased the helium pressure until the membrane broke. This produced a shock wave that swept into the gaseous mixture at high speed, momentarily creating temperatures of several thousand degrees. In seven separate experiments, at least four amino acids were left behind...
...process was remarkably efficient. Carl Sagan, director of Cornell's Planetary Studies Laboratory, calculates that as much as 36% of the ammonia was converted into amino acids-a far better yield than that obtained in tests using ultraviolet radiation. Reason: the temperature rises resulting from the shock waves were too brief to break up any of the newly formed molecules. Indeed, the shock-tube process worked so well that Sagan has suggested a highly practical application: a cheap method of making amino acids for protein food supplements to fight malnutrition...