Lymphocyte And Monocyte-macrophage System Flashcards
What is the monocyte–macrophage system also called?
The reticuloendothelial system
It consists of the body’s complement of monocytes and macrophages.
What are the two types of macrophages based on their mobility?
Mobile and fixed macrophages
Mobile macrophages can move throughout the body, while fixed macrophages are located in specific tissues.
Name one collection of fixed macrophages found in the liver.
Hepatic macrophages (Kupffer cells)
Kupffer cells are responsible for filtering and cleaning the blood in the liver.
What is one protective function of macrophages?
Phagocytosis
Macrophages engulf and digest cellular debris, pathogens, and other harmful substances.
What are cytokines?
Biologically active chemicals synthesized and released by macrophages
Examples include interleukin 1, which plays a role in inflammation and immune responses.
What role do macrophages play in inflammation?
They produce factors important in inflammation and repair
Macrophages help initiate and regulate the inflammatory response.
What is the lifespan of platelets?
8 to 11 days
After their lifespan, platelets are primarily destroyed by macrophages in the spleen.
What stimulates the production of platelets?
A fall in platelet count and thrombopoietin from the kidneys
Thrombopoietin is a hormone that promotes the synthesis of platelets.
What is the normal blood platelet count range?
200 × 10^9/l to 350 × 10^9/l
This translates to 200,000 to 350,000 platelets per mm3 of blood.
What type of cells do lymphocytes develop from?
Pluripotent stem cells in red bone marrow
These stem cells can differentiate into various types of blood cells, including lymphocytes.
What are the two distinct types of lymphocytes produced upon activation?
T-lymphocytes and B-lymphocytes
These lymphocyte types play crucial roles in the adaptive immune response.
Fill in the blank: Lymphocytes become _______ when they are able to respond to antigens.
Immunocompetent
Immunocompetence refers to the ability of lymphocytes to recognize and respond to foreign substances.
What are some examples of antigens that lymphocytes respond to?
- Abnormal cells (e.g., virus-invaded or cancer cells)
- Pollen
- Fungi
- Bacteria
- Large molecule drugs (e.g., penicillin, aspirin)
Antigens are substances that the immune system identifies as foreign.
What are platelets also known as?
Thrombocytes
Platelets play a crucial role in blood clotting and the cessation of bleeding.
Where are platelets derived from?
The cytoplasm of megakaryocytes in red bone marrow
Megakaryocytes are large bone marrow cells responsible for producing platelets.
