Crash Course : Immune system part 2

Adaptive (Specific) Immunity

The immune system's second line of defense; involves a targeted response with memory for specific

Humoral Immunity

Antibody-mediated immunity; driven by B cells and antibodies that target pathogens in body fluids.

B Lymphocyte (B Cell)

A type of white blood cell that, when activated, differentiates into antibody-producing plasma cells and memory cells.

Antigen

A molecule (often foreign) that can trigger an adaptive immune response by binding to specific receptors.

B Cell Receptor (BCR)

The membrane-bound antibody on a B cell's surface that binds a specific antigen.

Clonal Selection

The process where a lymphocyte (B or T cell) that binds its specific antigen is stimulated to proliferate into a clone of identical cells.

Plasma Cell

The short-lived, effector cell derived from a B cell; secretes large amounts of a specific antibody.

Memory B Cell

A long-lived B cell clone that remains after an infection, providing immunological memory for a faster secondary response

Antibody (Immunoglobulin)

A Y-shaped protein secreted by plasma cells that binds specifically to a unique antigen.

Neutralization

An antibody function where it blocks the binding site of a virus or toxin, preventing it from attaching to host cells.

Opsonization

The process where antibodies coat a pathogen, marking it for engulfment and destruction by phagocytes.

Complement System

A group of plasma proteins that, when activated (often by antibodies), enhance inflammation, opsonization, and cell lysis.

Immunological Memory

The adaptive immune system's ability to "remember" previous pathogens and mount a stronger, faster response upon re-exposure.

Vaccine

A biological preparation that provides active acquired immunity to a particular infectious disease by stimulating immune memory.

Active Immunity

Immunity that develops from the production of your own antibodies and memory cells after exposure to an antigen.