The book presents data on the functions and metabolism of mineralized tissues. The results of studying the state of bone tissue and calcium metabolism during space flights and in model studies are considered. The results of ground model studies of the effect of hypo- and ripergravity on bone strength characteristics are discussed. The role of hormonal and physicochemical factors in the mechanisms of changing ionrorulation in humans during space flights of various durations is analyzed. The effectiveness of various means of preventing electrolyte metabolism disorders and bone demineralization in the studied conditions was assessed. The concept of changes in mineral metabolism and bone tissue in hypogravitation is proposed. For biologists, physiologists, biochemists, specialists in space biology and aerospace medicine.