Final answer:
The lymphatic system is crucial for the development and function of B and T cells, both of which are produced in the bone marrow, while T cells mature in the thymus before joining B cells in secondary lymphoid organs to facilitate immune responses.
Step-by-step explanation:
The accurate statement regarding the lymphatic system activity is: B and T lymphocyte development begins in the bone marrow and ends in the peripheral lymphoid structures. Both B cells and T cells originate from hematopoietic stem cells in the bone marrow. B cells complete their maturation in the bone marrow itself, hence the name 'B cells'. In contrast, T cells migrate to the thymus, where they mature, earning the 'T' in their name.
After maturation, both B cells and T cells join other lymphocytes in the secondary lymphoid structures such as lymph nodes and the spleen to participate in the adaptive immune response. These lymphocytes are able to circulate throughout the body through the interconnection of the lymphatic and vascular systems, including the process of extravasation which permits their movement between the bloodstream and lymphatic vessels.
Once in secondary lymphoid organs, T and B cells are well-positioned to encounter antigens and initiate an immune response. Pathogens are typically filtered through these lymphoid structures where they are encountered by the prepared immune cells. Thus, the primary lymphoid organs are crucial for lymphocyte development, whereas secondary lymphoid organs are crucial for their immune functions.
B and T cells both originate from the bone marrow, where B cell maturation is completed. T cells migrate to the thymus for maturation, after which both types of lymphocytes function in immune responses within secondary lymphoid structures.