Question

The circulatory route through a lymphoid tissue for naive B cells that do not encounter specific antigen is?

1) bloodstream → HEV of lymphoid cortex → primary lymphoid folLiCle → efferent lymphatic vessel
2) afferent lymphatic vessel → primary lymphoid folLiCle → HEV of lymphoid cortex → efferent lymphatic vessel
3) afferent lymphatic vessel → medullary cords → primary lymphoid folLiCle → efferent lymphatic vessel
4) primary lymphoid folLiCle → HEV of lymphoid cortex → afferent lymphatic vessel → efferent lymphatic vessel
5) bloodstream → afferent lymphatic vessel → HEV of lymphoid cortex → efferent lymphatic vessel

Answer 1

The route for naive B cells through a lymphoid tissue when they do not encounter an antigen is: bloodstream → HEVs of lymphoid cortex → primary lymphoid follicle → efferent lymphatic vessel. The correct answer is option 1.

Step-by-step explanation:

The circulatory route through a lymphoid tissue for naive B cells that do not encounter a specific antigen is as follows: Naive B cells originate in the bone marrow and then travel via the bloodstream to the secondary lymphoid organs, such as lymph nodes. Upon reaching a lymph node, they enter through high endothelial venules (HEVs) in the lymphoid cortex. From there, they migrate into the primary lymphoid follicles to surveil for antigenic material. If they do not encounter their specific antigen, they will eventually exit the lymph node via efferent lymphatic vessels.

Therefore, the correct circulatory route for naive B cells through a lymphoid tissue when they do not encounter an antigen is:

1. Bloodstream
2. HEVs of lymphoid cortex
3. Primary lymphoid follicle
4. Efferent lymphatic vessel