Downing lymphatic system Flashcards
Primary lymphatic tissue?
Bone marrow
Thymus
Secondary lymphatic tissue?
MALT (mucosa associated lymphatic tissue or nodular non-encapsulated lymphatic tissue)
Encapsulated:
Lymph nodes
Spleen
Two types of small lymphocytes of the lymphatic tissue?
B-cells
T-cells
Two types of Large lymphocytes of the lymphatic tissue?
Activated lymphocytes
NK (natural killer) lymphocytes
What type of cells mostly make up the germinal center of a secondary lymphatic nodule?
Large and medium lymphocytes (mostly B-cells)
- lymphoblasts
- mitotic
Small lymphocytes (B and T)
- more numerous; mitosis not common
- enlarged and divide when stimulated
Macrophages (APCs)
Follicular dendritic cells (FDCs)
Plasma cells (periphery)
What type of lymphatic tissue does NOT contain lymphatic nodules?
Thymus
What’s an example of a non-encapsulated nodular lymphatic tissue?
tonsils
Main function of non-encapsulated lymphatic tissue?
trapping antigen, B cell proliferation, destruction of antigen
Where is lymph filtered?
lymph nodes (macrophages)
Subdivision of lymph node containing T cells?
Deep cortex (paracortex)
Journey of lymph through a node:
Afferent lymphatic vessels
subcapsular sinus
trabecular sinus
paracortical sinus
medullary sinus
efferent lymphatic vessel
What is the difference in the post-capillary venules between the outer and deep corteces of the lymph nodes?
Outer venules have simple squamous epithelium
Deep venules have simple cuboidal endothelium
Three function of the lymph node?
Lymph filter
Lymphocyte production
antibody production (plasma cells)
What is a very important job of epithelial reticular cells in the thymus?
help form blood-thymus barrier to protect developing t-cells from exposure to antigens
major blood supply to the thymus?
internal thoracic and inferior thyroid arteries
