Final answer:
Developing B cells are typically smaller than stromal cells. B cells range from 6-17 µm in diameter, whereas stromal cells vary more in size and perform different functions. B cells differentiate within the bone marrow, while T cells mature in the thymus gland.
Step-by-step explanation:
In the context of the immune system's cells, developing B cells are typically smaller in size compared to stromal cells. B cells, as a type of lymphocyte, have a characteristic size that varies from 6 to 17 µm in diameter, with the smaller B cells being around 6-9 µm and larger ones reaching up to 14-17 µm. On the other hand, stromal cells in the bone marrow provide structural support and are typically larger and vary more significantly in size due to their diverse functions. As B cells differentiate and mature within the red bone marrow, they exist amongst these stromal cells which can be considered as a part of their maturation environment.
B cells are named for the 'bone' in bone marrow where they grow larger, in contrast to T cells that mature in the thymus gland. Despite both being lymphocytes, B cells and T cells are morphologically identical, possessing a large central nucleus surrounded by a thin layer of cytoplasm and differing mainly in their surface protein markers. Both types initially develop from bone marrow but take different paths in maturation, with B cells staying within the bone marrow and T cells migrating to the thymus.