The structure of spongiosa is composed of a network of trabeculae, which are aligned along lines of stress to provide optimal support and strength. The spaces between the trabeculae are often filled with bone marrow, which can be either red or yellow depending on the bone’s location and the individual’s age. Red bone marrow is involved in hematopoiesis, the process of blood cell formation, while yellow bone marrow primarily consists of adipose tissue.