Why is it important for scientists to develop a way to grow tissues that have a built-in system to supply blood? a lack of blood flow determines the number of cell layers that can survive when they are transplanted. a lack of blood flow determines the types of tissues that can be grown in culture. a lack of blood flow determines the amount of culture medium that is needed to keep a tissue alive. a lack of blood flow determines the amount of time a tissue can be kept alive in culture.