The Lymphatic System Flashcards
What is immunity and resistance?
It is the ability to use body defences to ward off diseases or damage
What are the 2 types of immunity?
Innate and adaptive
What is innate immunity?
These are the defences that are present at birth. They are always available and will provide rapid responses to protect us against disease
What is adaptive immunity?
These are the defences that involve specific recognition of a microbe. It response to a specific microbe that it adapts to or it adjusts to handle that specific microbe
What is a lymphocyte?
A white blood cell that participates in the immune response
What are the 2 lymphocytes found in adaptive immunity?
T Lymphocytes (T cells) and B lymphocytes (B cells)
What does the lymphatic system consist of?
Lymph vessels including - lymphatic capillaries, lymphatic vessels and lymphatic trunks and ducts.
Organs - lymph nodes, tonsils, spleen, thymus, red bone marrow and appendix
What is lymphatic tissue?
It is a specialised form of connective tissue that contains a large number of lymphocytes
What are the 3 primary functions of the lymphatic system?
1 - drains excess interstitial fluid
2 - transports dietary lipids
3 - carries out immune responses
How is interstitial fluid formed?
Components of blood plasma filter out from blood capillary walls to form the fluid
What do lymphatic vessels begin as?
lymphatic capillaries in tissue spaces between cells.
What do lymphatic capillaries merge to form?
lymphatic vessels
What flows through the lymph nodes?
Lymph
What are located in intervals along the lymphatic vessels?
Lymph nodes
What drains into the thoracic duct from the lymphatic vessels?
Lymph
What does the thoracic duct empty it’s lymph into?
Into the left internal jugular and the left subclavian vein.
Where does the lymphatic vessel empty it’s lymph into?
The thoracic duct or the right lymphatic duct
What does the right lymphatic duct empty it’s lymph into?
The right internal jugular or right subclavian vein.
What is a lymph node?
Masses of B and T cells surrounded by a capsule
What are the 2 pumps that bring back venous blood to the heart to maintain the flow of lymph?
Respiratory pump and skeletal muscle pump
What are primary lymphatic organs for?
They are the sites where stem cells divide and develop into mature T and B cells.
What are 2 primary lymphatic organs?
Red bone marrow and the thymus
What do the stem cells in the red bone marrow do?
Mature the B cells
What do the stem cells in the thymus do?
Mature into functioning T cells
What are the secondary lymphatic organs?
Lymph nodes, spleen and lymphatic nodules
What happens at the secondary lymphatic organ sites?
This is where the immunity responses occur
What is the thymus?
And what does is contain?
This is a 2 lobed organ that is located posterior to the sternum and medial to the lungs.
It contains large numbers of T cells and macrophages
What do lymph nodes contain?
B cells that develop into plasma cells, T cells, dendritic cells and macrophages.
How does lymph go through the lymphatic vessels?
They enter through the afferent lymphatic vessels and exits through the efferent lymphatic vessels
What is the spleen?
It is the largest single mass of lymphatic tissue. It lies between the stomach and the diaphragm. It contains 2 types of tissue - the white pulp and the red pulp
What are the 2 types of tissue found in the spleen?
The white pulp which is where the B and T cells carry out the immunity responses
The Red pulp which is blood filled sinuses where worn out blood cells and platelets are removed
What is a pathogen?
A disease causing organism - bacteria, viruses, fungi and parasites
What is an antigen?
A substance that induces the production of antibodies
What is an antibody?
An immunoglobulin that binds to specific antigens to facilitate their breakdown and removal from the body