Immunology 2 Flashcards
What are the functions of the lymphatic system?
Drainage of tissue
Absorption and transport of fatty acids and fats
Immunity
What aspect of the lymphatic system is responsible for circulation and production of lymphocytes?
Spleen, thymus and bone marrow
How is lymph fluid formed?
Lymph is the fluid that is formed when the interstitial fluid containing dissolved components of the blood enters the conduits of the lymphatic system.
How is the lymph pumped through the body?
Contractions of skeletal muscles
Where do lymphatic vessels carry their fluid?
Away from tissues
What is the name given to the smallest lymphatic vessel?
Lymphatic capillaries
Why can’t fluid escape lymphatic vessels but it can enter?
The walls are composed of endothelium in which simple squamous cells overlap to from one-way valves
Where do both lymphatic trunks drain their fluid?
The blood circulatory system at the right and left subclavian vein
Where does Ab enter the blood from?
The lymphatic system
Where is the recognition phase of the adaptive immune system?
Secondary lymphoid organs, include lymph nodes, the spleen and mucosal associated lymphoid tissue.
Site of lymphocyte activation by antigens
Where do B cells and T cells originate and receive their training?
Primary lymphoid organs - the thymus and the bone marrow
Which part of the bone marrow can be considered lymphatic tissue?
The stem cells in the marrow from which lymphocytes develop, but not in the red bone marrow because there is no lymphatic tissue in the myeloid tissue (tissue which is able to form hematopoeisis
What is a thymocyte?
A t cell precursor
What is the epitone?
The part of the antigen that can be recognised
What is the main function of a spleen?
Acts as a filter
What is meant by white pulp in the spleen?
Small white spots consisting mainly of lymphatic nodules
What is red pulp?
Soft, red, blood rich tissue
What is the function of high endothelial venules?
They are specialised areas in blood vessels which allow lymphocytes in the blood to directly enter the lymph nodes. Although they do not allow backward passage of lymphocytes back into the blood
Where can you find lymph nodes?
Located at intervals along the route the lymph takes while being transported back to the blood
What is lymph separated into once it enters the lymph node?
B cells and T cells, the lymph node is a dating bar for antigen and lymphocyte
Where are the HEV found in lymph nodes?
On the incoming arterioles and outgoing veins
Give an example of the mucosal lymphatic associated tissue
Peyers patches - found in the small intestine - part of the secondary lymphoid tissue
How do peyers patches function?
M cells on peyers patches sample Ag from the lumen of the intestine and transport it to the peyers patch using endosomes. This sample then joins the lymph of the peyers patch and travels to the lymph node that drains the peyers patch
What type of tissue are tonsils?
Lymphoid tissue