HISTO - Lymphatic System Flashcards
What are the 3 major functions of the Lymphatic system?
- Drain excess interstistial fluid - return to bloodstream to help maintain normal blood volume.
- Immune Response - produce, maintain, and distribute lymphocytes.
- Provide an alternative transportation route fro hormones, nutrients and Waste products.
What are the 3 types of lymphocytes?
- B cells = produce and secrete antibodies along with their derivative cell; involved with humoral immunity; 20-30% of circulating lymphocytes.
- T cells = Differentiate in the thymus; attach and destroy cells; involved with cell-mediated immunity; 60-80% of circulating lymphocytes.
- Natural Killer cells = kill certain transformed cells; 5-10% of circulating lymphocytes
What is Diffuse Lymphatic tissue?
Accumulations of lymphocytes in the lamina propria of the alimentary canal, as well as respiratory, urinary and reproductive tracts.
- no surrounding capsule
- also find plasma cells and eosinophils.
What are lymphatic nodules?
similar to diffuse lymphatic tissue, it is accumulations of lymphocytes in the wall of alimentary canal, as well as respiratory, urinary and reproductive tracts.
- No surrounding capsule
- sharply defined
- Meshwork of reticular fibers
- Lymphocytes, plasma cells, eosinophils.
What are the 2 types of Lymphatic nodules?
- Primary Nodule = aggregation of primarily small lymphocytes
- Secondary Nodule = will have a germinal center and a mantle zone (follicular dendritic cells (FDC’s) are present in germinal centers.
True or False, Lymphatic nodules are normally found randomly dispersed by themselves.
True.
However in central location of the alimentary canal, they are grouped together (aggregated lymphatic nodules).
Where are the 2 regions of aggregated lymphatic nodules?
- Tonsils = create ring around entrance to the oropharynx and the nasopharynx.
- Peyer’s patches = in ileum.
What is MALT?
Mucous associated lymphatic tissue.
What is GALT?
Gut associated lymphatic tissue (associated with the alimentary canal)
What is BALT?
Bronchus associated lymphatic tissue; associated with the respiratory system
What are the supporting cells?
Reticular cells, monocytes, macrophages, neutrophils, basophils, eosinophils, dendritic cells, follicular dendritic cells, langerhans cells, and epithelioreticular cells.
______ is a capsule organ along the pathway of lymphatic system,
Lymph node
What is the function of the lymph node?
Filtering system
What are the 5 parts of the Lymph node?
- Capsule
- Trabeculae
- Reticular Tissue/Meshwork
- Cortex
- Medulla
Describe the layers of the cortex of the lymph node….
- Superficial (Nodular) cortex.
- Primary & secondary nodules (Secondary have germinal centers) - Deep cortex (paracortex)
What are the 2 structures of the lymph node medulla?
- Medullary cords (Purple bean shapes made of purple dots)
2. Medullary sinuses
What are the 4 cells of the reticular Meshwork?
- Reticular cells
- Dendritic cells
- Macrophages
- Follicular Dendritic cells
What is the flow of lymph through the lymph node?
Afferent lymph vessel —> subcapsular (cortical) sinus—>trabecular sinus—>Medullary sinus—>Efferent lymph vessel
The Thymus is the site of, thymic cell education…What occurs in this process?
T cells mature and differentiate into immunocompetent T cells.
What is the Function of the Spleen?
Filters and monitors the blood immunologically just at the lymph nodes monitor lymph.
The spleen consists of a variety of pulps….what are they?
just kidding its only 2 pulps….The Red and white Pulp.
Describe the red pulp of the spleen…
Consists of blood filled venous sinuses surrounded by cords of splenic tissue called splenic cords.
- The cords consist of rbc’s, macropahges, lymphocytes, plasma cells, and granulocytes.
- Primary role of red pulp is blood filtration!
Describe the White Pulp of the Spleen…
lymphatic tissue consisting mostly of lymphocytes lymphocytes aggregate around branches of splenic artery creating a periarterial lymphatic sheaths.
* Function of white Pulp is to carry out immune functions similar to lymph nodes.
