The much-studied Murchison meteorite is generally used as the standard reference for organic compounds in extraterrestrial material. Amino acids and other organic compounds important in contemporary biochemistry are thought to have been delivered to the early Earth by asteroids and comets, where they may have played a role in the origin of life. Polyhydroxylated compounds (polyols) such as sugars, sugar alcohols and sugar acids are vital to all known lifeforms-they are components of nucleic acids (RNA, DNA), cell membranes and also act as energy sources.
View Article and Find Full Text PDFJ Gravit Physiol
October 1999
To study renal handling of urinary electrolytes from male Fisher 344 rats during spaceflight, waste pads were obtained from cages flown in space and from cages used for ground controls. Pads were obtained from cages in which animals were group-housed (n=6 animals/cage) (Animal Enclosure Module; AEM) for 12 days or individually housed (2 animals/divided cage) (Research Animal Holding Facility; RAHF) for 19 days. Pads were washed, and extracts analyzed for sodium, potassium, chloride, calcium, and creatinine concentrations.
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