Lymphocytes and lymphatic organs Flashcards
What are the three main types of blood cells produced in red bone marrow?
Red blood cells (RBCs or erythrocytes), white blood cells (WBCs or leukocytes), and platelets (thrombocytes)
All blood cells are produced in red bone marrow.
What percentage of WBCs are lymphocytes?
Twenty-five percent
Lymphocytes are vital to immune responses.
What are the two main types of lymphocytes?
B-cells and T-cells
B-cells and T-cells are types of lymphocytes.
Where do B-cells complete their maturation?
Red bone marrow
B-cells mature in red bone marrow before entering the bloodstream.
Where do T-cells complete their maturation?
Thymus
T-cells mature in the thymus before entering the bloodstream and traveling to lymphatic organs.
What hormones does the thymus produce to stimulate the maturation of lymphocytes?
Thymosin and thymopoietin
Thymosin and thymopoietin stimulate the maturation of lymphocytes in the thymus.
What are the primary lymphatic organs involved with?
The production and maturation of lymphocytes.
Primary lymphatic organs are red bone marrow and the thymus.
Where are B- and T-cells formed?
B-cells are formed in red bone marrow. T-cells complete their maturation in the thymus.
Mature B-cells migrate to secondary lymphatic structures such as lymph nodes. T-cells also migrate to secondary lymphatic structures.
What are secondary lymphatic organs populated by?
B-cells and T-cells.
Secondary lymphatic organs include lymph nodes, mucosa-associated lymphoid tissue (MALT), and the spleen.
What is the function of lymph nodes?
Filtering lymph.
Lymph nodes are the only structures that filter lymph. They destroy or deactivate pathogens, cancer cells, damaged cells, and cellular debris.
What are MALTs and what is their function?
Small groups of lymphatic tissue along the respiratory and GI tracts that help protect the body from pathogens and invaders.
Tonsils, Peyer Patches, and Vermiform Appendix are examples of MALTs.
Where is the spleen located and what is its function?
In the upper left quadrant of the abdomen. It filters blood, reacts to pathogens, stores blood, and destroys old RBCs.
The spleen releases stored lymphocytes when needed and can release blood into the bloodstream during blood loss.
