Immune system Flashcards
Immune system (19 cards)
What are the two main components of the immune system?
Innate immunity and adaptive immunity
Innate immunity is present in all animals, while adaptive immunity is only found in vertebrates.
What is the role of immune cells such as macrophages and lymphocytes?
Recognize and destroy pathogens
This includes distinguishing self from nonself.
What are the physical barrier defenses in innate immunity?
Skin & exoskeleton, mucous membranes
These prevent pathogen entry and trap pathogens.
What is phagocytosis?
The process by which white blood cells engulf and digest pathogens
This includes cells like macrophages and neutrophils.
What do Toll-like receptors (TLRs) do?
Recognize pathogen-specific molecules and trigger immune responses
TLRs are crucial for innate immunity.
What is the function of natural killer (NK) cells?
Destroy virus-infected or cancerous cells
They do this by releasing cell-killing proteins.
Name two antimicrobial proteins involved in innate immunity.
Interferons and the complement system
Interferons inhibit viral replication, while the complement system leads to pathogen destruction.
What triggers the inflammatory response?
Histamine from mast cells
Histamine increases blood flow and permeability.
What is the primary function of B cells in the immune response?
Produce antibodies and provide long-term immunity
B cells differentiate into plasma cells and memory B cells.
What are antigens?
Foreign molecules that trigger an immune response
They are recognized by B and T cells.
What is the role of helper T cells (CD4+)?
Activate B cells and cytotoxic T cells
They also secrete cytokines to coordinate the immune response.
What is clonal selection?
The process where an antigen binds to a specific B or T cell, leading to cell proliferation
This creates a clone of cells specific to that antigen.
True or False: The secondary immune response is slower than the primary immune response.
False
The secondary response is faster and stronger due to memory cells.
What is antigenic variation?
The change of surface proteins by pathogens
This helps pathogens evade the immune system.
What is passive immunity?
Immunity acquired through the transfer of antibodies
It can be natural (from mother to child) or artificial (injection of antibodies).
What triggers allergies?
Hypersensitive reactions to harmless antigens (allergens)
IgE antibodies play a key role in these reactions.
Name two autoimmune diseases.
Lupus and Type 1 Diabetes
In lupus, antibodies attack DNA; in Type 1 Diabetes, immune cells destroy insulin-producing cells.
What is SCID?
Severe combined immunodeficiency
It is an example of an inborn immunodeficiency.
What are the effects of stress and lack of sleep on the immune system?
Impair immune function
Chronic stress and sleep deprivation can weaken immune defenses.
