Immune Tissues

Question 1

1. Name the primary lymphatic tissues (2)
2. Where do T and B cells
   a) develop?
   b) mature?
3. name the secondary lymphatic tissues (3)
4. what is the role of the secondary lymphatic tissues?
5. describe the general characteristics of lymphoid tissue

Answer 1

1. bone marrow and thymus
   2a) b and t cells develop in the bone marrow
   2b) B cells continue to mature in the bone marrow. T cells exit the bone marrow and mature in the thymus
2. lymph nodes, spleen and mucosal associated lymphoid tissue (e.g. tonsils)
3. site of acquired immune response generation. Lymphocytes reside here.
4. encapsulated, vascularised and compartmentalised.

Question 2

1. what is the primary role of the lymphatic system?
2. describe the structure of lymph capillaries
3. what to superficial lymphatics follow?
4. Where do superficial lymphatics flow into?
5. What do deep lymphatics follow?
6. Where do deep lymphatics drain?

Answer 2

1. to maintain fluid balance by returning lymph to the blood
2. originate as closed tubes in almost all tissues. Capillary wall is constructed of overlapping endothelial cells that respond to flow pressure. Valves facilitate unidirectional movement
3. superficial veins
4. lymph nodes in axillary, inguinal or cervical areas, from which they drain into deep lymphatics
5. main vessels
6. lymph from lower 3/4 of body drains into left brachiocephalic vein via thoracic duct
   lymph from upper 1/4 of body drains into right brachiocephalic vein

Question 3

1. what structure:
   a) delivers blood to a lymph node?
   b) delivers lymph to a lymph node?
   c) takes lymph away from a lymph node?
2. where do
   a) T cells reside?
   b) B cells reside?
   c) B cells mature?

Answer 3

1a) artery
1b) afferent lymphatic vessel
1c) efferent lymphatic vessel
2a) paracortex
2b) lymphoid follicle
2c) germinal centre (within a follicle)