Method of holding the living body, a method of testing a biological, growth method of a living body, living body holding sheet and the biological treatment device

A method of arranging a large number of living bodies, such as cells, embryos, or organisms rapidly, individually, and one by one, a holding sheet for the method, and a device for processing the living bodies. The method of holding living bodies includes using a sheet in which multiple through-holes with a size capable of holding one of the target living bodies, but not capable of holding two or more of the living bodies, are provided, to thereby arrange and hold the living bodies one by one in the multiple through-holes in the sheet together with a liquid.