Chapter 21: Lymphatic & Immune Flashcards
Main components of the immune system
Lymphochytes
Lymphoid tissue
Lymphoid organs
Components of the lymphatic system
Lymph capillaries Collecting vessels Lymph nodes Lymph trunk Lymph duct
Function: Lymph capillaries
Highly permeable with flap like minivalves that allow easy uptake of fluid and proteins
Function: Collecting vessels
Have one way valve like veins and use skeletal muscle pumps to move lymph toward the heart
Function: Lymph node
Filters afferent lymphatic flow and provides an opportunity to recognize “bacterial strangers” as lymph percolates through its medullary sinuses
- Antigen presenting cells look for naive T cell that recognize the antigen they carry
- a match activates the T cell and selects it for cloning and subsequently results in antigen specific antibody production by a B cell
T or F: in the lymph node - a match activates the T cell and selects it for cloning and subsequently results in antigen specific antibody production by a B cell
True
T or F: in the lymph node - Antigen presenting cells look for naive T cell that recognize the antigen they carry
True
- antigen presenting cells: macrophages, dendritic cells and B cells
What are the 5 Major lymphatic trunks
Lumbar Intestinal Bronchiomediastinal Subclavian Jugular
____ is a major lymphatic channel returning lymph to vascular space
Thoracic duct
- commonly occurs at the junction of left subclavian and left internal jugular
3 functions of the lymphatics
- Return excess tissue to bloodstream
- Return leaked protein
- Carry absorbed fat from intestinal lacteals to venous circulation
B cells
divide to produce plasma cells
- secrete antibodies that bind with soluble antigens, marking them for phagocytes
Cytotoxic (CD8) T cells
Directly lyse the “foreign” cells
- a virus infected cell or cancer cell
lyse; rupture of cell wall
Helper T cells
- Help activate B cells to secrete antibodies
- Help macrophages to destroy ingested microbes
- Help activate cytotoxic T cells to kill infected target cells.
Humoral Immunity
Active B cells become plasma cells that produce antigen specific antibodies and memory cells that are ready for any later exposure to the same antigen
T or F: T cells have their origin in the bone marrow but then go to the thymus to learn self tolerance and become immunocompetent
True
self tolerant: not to attack themselves
