Defence against disease - white blood cells Flashcards
What are phagocytes?
Phagocytes are white blood cells produced continuously in the bone marrow
What is the primary function of phagocytes?
They are responsible for removing dead cells and invasive microorganisms
How do phagocytes move to the site of infection?
Phagocytes move in an amoeboid movement
What process do phagocytes use to engulf pathogens?
Endocytosis
What do phagocytes use to digest pathogens?
Enzymes stored within lysosomes
What are lymphocytes?
Lymphocytes are a type of white blood cell involved in the specific immune response
What are the two types of lymphocytes?
- T cells
- B cells
Where are T cells produced and matured?
Produced in the bone marrow and mature in the thymus
What are T cell receptors?
Specific cell surface receptors on mature T cells
What activates T cells?
When they encounter and bind to their specific antigen on an antigen-presenting cell
What types of cells can be antigen-presenting cells?
- Macrophages
- Infected body cells
- Pathogens
What happens to activated T cells?
They divide by mitosis to increase in number
What is the result of T cell division by mitosis?
Produces genetically identical cells or clones
Where do B cells mature?
B cells remain in the bone marrow as they mature
What are antibody receptors?
Specific receptors on the surface of B cells that are actually antibodies
What forms when a B cell binds to an antigen?
An antigen-antibody complex
What activates B cells?
Binding to their specific antigen and cell signalling from T helper cells
What types of cells do activated B cells produce?
- Effector cells
- Memory cells
What do effector cells differentiate into?
Plasma cells
What is the function of plasma cells?
Produce specific antibodies to combat non-self antigens
What is the role of memory cells?
Remain in the blood for a faster immune response to the same pathogen in the future
