The concept and understanding the effects of microgravity on the functions of living cells (both eukaryotic and prokaryotic) is important as it accounts for the safety and health of astronauts during space flight. It?s a fundamental question regarding the evolution of terrestrial life that how cells sense gravity and adapt in its absence and the mechanism of general mechanosensory responses of all living organisms. Other molecular organizations are also altered in the microgravity environment. The mass and architecture of the skeletal system adapt, to some extent, also influenced by their mechanical environment. Biochemical data of astronauts and histomorphometric analysis of rat bones show that the change in bone mass formation appears to be due in part to decreased osteoblast differentiation, matrix maturation and mineralization. Most of the microgravity researches on plant cells are concentrated on their cell root growth pattern, development of cell wall and gene regulation pattern. Most of the researches on plant cells have been done on Arabidopsis thaliana. Each of these studies has been found very important applications in space researches as well as for the future design of materials on earth.