The Lymphatic System (7.4) Flashcards
Describe lymphatic system
Body system that transports immune cells including APCs throughout the body
State what immune response the lymphatic system plays a key role in
Adaptive immune response
State what the lymphatic system transports
Immune cells
State the 4 major roles of the lymphatic system
- returning fluid that seeps out of the blood vessels back to the circulatory system
- absorbing/transporting fatty acids from the digestive system
- providing a place for lymphocytes to mature
- transporting lymphocytes and APCs to lymph nodes
State to where invading pathogens are transported to by the lymphatic system
Invading pathogens are transported in the lymph to the lymph nodes
State what occurs to the invading pathogens that penetrate the lymph nodes
Trapped and destroyed by phagocytes and lymphocytes
State what causes lymph nodes to swell during an infection
Trapping and destroying of bacteria, viruses and cancer cells
State the 4 structures that make up the lymphatic system
- lymph
- lymphatic vessels
- primary lymphoid organs/tissues
- secondary lymphoid organs/tissues
Describe interstitial fluid
Drained into lymphatic vessels
Describe lymph
Colourless fluid that contains white blood cells, bathes tissues and travels through the lymphatic system.
State what immune cells are contained within the lymph
- lymphocytes
- phagocytes
State 2 regions where lymphatic vessels are absent within the body
- bones
2. CNS
State by which process cells and fluid can pass between blood and lymph capillaries
Extravasation
Describe primary lymphoid organs
Major organs of the lymphatic system
Describe secondary lymphoid organs and tissues
Organs and tissues of the lymphatic system in which adaptive immune responses are initiated
State why the thymus is considered a primary lymphoid organ
Role in maturation of T lymphoctes
State what occurs to thymus structure that contributes to a higher risk of infection and cancer that comes with age
Shrinking of the thymus
State by what tissues lymphocytes are activated in the adaptive immune response
Secondary lymphoid tissues
State what lymph nodes act as
Filters
State what substances lymph nodes trap in the lymphatic system
- trapping foreign particles
- cellular waste
- toxins
- pathogens
State what the structure of lymph nodes maximises
Chance of encounters between antigens and immune cells
State where APC in body tissue migrate to after phagocytosing pathogens
Lymph nodes
State why APCs migrate to lymph nodes after phagocytosing pathogens
Present foreign antigens to helper T lymphocytes
State whether the flow of lymph through the lymphatic system is one directional or two directional
One directional
State where B and T lymphocytes interact within the lymphatic system
Follicles of the lymph nodes
State what B lymphocytes that identify an antigen in the lymphatic system undergo
Clonal expansion/differentiation
State a possible cause of lymph node expansion
Cell proliferation
State what the spleens primary function in the lymphatic system is
Control the number of red blood cells in the body by destroying defective
State what the spleen stores
Quarter of body’s lymphocytes
Outline the effect of spleen removal on B lymphocyte maturation
Not disastrous. B lymphocytes can continue to mature within secondary lymphoid tissues.
State 2 examples of primary organs of the lymphatic system
- bone marrow
2. thymus
State 3 examples of secondary organs of the lymphatic system
- spleen
- tonsils
- lymph nodes
State whether or not antigens can be presented to B cells
No.
