PRINCIPAL INVESTIGATOR(S ) : Brenda Buckhold, John V. Slater, I. L. Silver, 



Tracy C. H. Yang, and C. A. Thomas 



EXPERIMENT TITLE/NUMBER : Some Effects of Spaceflight on the Flour Beetle, 



Tribolium confusum , P-1039 



PROGRAM/MISSION : Biosatellite II 



CLASSIFICATION : Animal .- Flour beetle ( Tribolium confusum ) 



DISCIPLINE(S) : Radiobiology, Genetics, Behavioral science 



OBJECTIVES : To study the effect of weightlessness and the combined effects of 

 gamma radiation and weightlessness on somatic wing development, germ cells, 

 and the pupal period in the flour beetle. 



PROTOCOL : 720 T ribolium pupae between 19 and 27 hrs old were orbited, half in 

 the presence of Sr and half shielded from it. Two-thirds of each pupae 

 group had received a preradiation dose (1350r) of 180 keV X-rays. Identical 

 Earth controls were maintained. All were maintained at 85 F. Upon return, 

 pupal period, wing abnormalities, and genetic damage was determined by mating 

 experiment beetles with the controls. 



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 EQUIPMENT : Three housing compartments, LiF disc dosimeters, Sr source. 



RESULTS : Pupal period, wing abnormalities, and dominant lethality were 

 significantly increased. "Split" mutation increased from ground values of 30% 

 to 45%. 



CONCLUSIONS : Some factor in space flight, probably weightlessness, either 

 facilitated the development of radiation induced chromosome breaks and/or DNA 

 damage in the meiotic cells (oocytes) or hindered the normal correction of 

 such errors. Another possible explanation is a temperature drop of the flight 

 samples that occurred between separation and retrieval of the flight capsule. 



PUBLICATIONS : 101, 102, 103, 104, 105, 479, 480, 481, 546 



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