Spaceflight effects on structural and some biochemical parameters of Brassica rapa photosynthetic apparatus.

Chloroplasts play a crucial role in sustaining life on Earth by their dual property in performing the primary fixation of carbon and also in releasing oxygen for use in respiration. Collection of light and its transformation into chemical energy occurs in a thylakoid membrane which is one of the most remarkable transducing systems in the biological world. In order for the light-dependent reactions could take place, a high degree of molecular organization of its constituents is needed. Some results obtained in the framework of the Collaborative Ukrainian Experiment mission (STS-87) which was performed on board of the space shuttle "Columbia" are presented in the given paper. A goal of the study was to obtain data on some parameters of photosynthetic apparatus, namely the chloroplast structure, pigment content and lipid composition of Brassica rapa plants grown in microgravity.