#1-immunology =Introduction to Immunity and the Immune System

These flashcards cover key terms and definitions related to the introduction of immunology and the immune system.

Immunology

The study of a host’s reactions to foreign substances.

Antigens

Foreign substances that attack the immune system and induce a host response.

Innate Immunity

Natural immunity that the body is born with; it is nonspecific and provides immediate responses to pathogens.

Adaptive Immunity

Characterized by specificity for each antigen and the ability to generate immune memory.

Inflammation

A response caused by chemotactic factors attracting cells to the site of infection or injury.

Chemotactic Factors

Substances produced to attract immune cells to areas of infection or injury.

Phagocytes

Cells that engulf and digest foreign particles; includes macrophages and neutrophils.

CD4 T-cells

Helper T-cells that assist other cells in producing an immune response.

CD8 T-cells

Cytotoxic T-cells that attack infected cells, leading to cell death.

MHC (Major Histocompatibility Complex)

Molecules on the surface of cells that present antigens to T-cells.

Natural Killer (NK) Cells

Innate immune cells that kill virally infected or cancerous cells without prior exposure.

B Cells

Lymphocytes that produce antibodies as part of the humoral immune response.

T Cells

Lymphocytes that perform various immune functions, including helper and cytotoxic roles.

Bone Marrow

Primary lymphoid organ that produces blood cells and is the maturation site for B cells.

Thymus

Primary lymphoid organ that is the site for maturation of T cells.

Lymph Nodes

Secondary lymphoid organs that filter lymph fluid and host immune responses.

Spleen

Largest secondary lymphoid organ involved in filtering blood and mounting immune responses.

MALT (Mucosal-Associated Lymphoid Tissue)

Tissues that sample antigens at mucosal surfaces, acting as a first line of defense.

Summary of Innate Immunity

Characterized by immediate response and nonspecificity.

Summary of Adaptive Immunity

Characterized by specificity, memory, and dependence on lymphocytes.