The results of biological studies made on board the Voskhod and Voskhod 2 spaceships.

The biological effects of flight and outer space factors were studied on biological specimens of various organization, viz. spiderwort microspores, dry seeds of the pine tree, wheat, onion and of other higher plants as well as on lysogenic bacteria and wine flies. Furthermore, lysogenic bacteria were studied for the effectiveness of a number of well known ray-proof substances (such as mercaptopropylamine, 5-methoxytriptamine, etc.). The specimens were secured in special containers both on board the spaceships and in the hip pockets of the astronaut Leonov's spacesuit. Biological effectiveness of the factors was evaluated by means of cytogenic, genetic and microbiological procedures. The analysis of the data obtained has shown that under the impact of the complex of flight and outer space factors, including ionizing radiation, both qualitative and quantitative changes occurred in the hereditary structures of some of the specimens, viz.: wheat seeds, spiderwort microspores and lysogenic bacteria. These changes were similar to the effects recorded in the flights of Vostok-2, 3, 6. As compared to the controls, an enlargement was found in the cells of wheat sprout radicles, accompanied by chromosome rearrangements (N. L. Deloney et al.). Increased phage production by lysogenic bacteria (N. N. Zhukov-Verezhnikov, N. I. Rybakov et al.) and impairment of the mitosis mechanism in the spiderwort macrospores were demonstrated (N. L. Deloney, etc.). Higher frequency of dominant lethals and more frequent than normal chromosome indivergence in the wine flies were recorded. Quantitatively, the recorded drifts were insignificant (as was the case with the 'Vostok' spaceships' flights). Of interest are the results of the experiments on spiderwort microspores carried out with B. B. Yegorov's participation. The data obtained show that 1) during the mitosis stage spiderwort microspores show differing sensitivity to the space flight factors, and that 2) the mitosis stages support the previous hypothesis that impairment of the mitosis mechanism is due to the state of weightlessness, while chromosome rearrangements are chiefly induced by the effects of the complex of factors related to the take-off and touch-down stages of the flight. (N. L. Deloney et al.). The analysis of beta-mercaptopropylamine and 5-methoxytriptamine tests indicates that these substances significantly reduce the phage producing activities of the lysogenic bacteria not only blocking the induced phage production but reducing the amount of spontaneous phage production as well (N. N. Zhukov-Verezhnikov, N. I. Rybakov et al.). Thus, the results of biological experiments on various specimens with differing degrees of radiosensitivity agree well among themselves and are consistent with the data on the dosage of space radiation.