Histology of Immune System: Primary Lymphoid Tissues Flashcards
What is primary lymphoid tissues?
Immature lymphocytes acquire receptors to recognise antigen
Name the primary lymphoid organs
Thymus and bone marrow
What matures in the thymus?
T Lymphocytes
What matures in bone marrow?
B-Lymphocytes
What is secondary lymphoid tissue?
Lymphocytes are activated in response to antigen
Name the secondary lymphoid organs
Spleen
Lymph nodes
Mucosal associated lymphoid tissue - tonsils, peyer’s patches, mucosae of GIT, respiratory and GU tracts
What is immunocompetence?
Ability to recognise foreign antigens
Name the lymphoid cells
Lymphocytes
Antigen Presenting cells
Reticular cells
What is the dominant organelle in lymphocytes?
Nucleus forms the majority of the cytoplasm
What is the role of antigen presenting cells?
Phagocytosis of foreign substances and help activate T cells
Name the Antigen Presenting cells
Macrophages
Dendritic cells
B lymphocytes
What is the role of reticular cells?
Produce stroma that supports other cells in lymphoid organs
Which part of the thymus has the most mature T cells and where has the least?
Cortex has less mature T cells
Medulla has more mature T cells
What cells are present in the thymus?
Lymphocytes
Macrophages
Reticular/Epithelial cells
What is rare in the thymus?
Reticular fibres
