Immune System Vocabulary

Flashcards on the Immune System

Pathogen

A living organism that enters the body and can be harmful

Host

The organism that the pathogen enters

Virulence

How harmful a pathogen can be in a relative way

Virus

Non-living pathogens that consist of a DNA or RNA genome wrapped in a protein coat called a capsid

PAMPs

Pathogen-associated molecular patterns on the pathogen's surface recognized as foreign

Innate Immunity

Immune response involving physical and chemical barriers and inflammatory response

Skin

Resilient physical barrier that prevents microbe entry

Mucous Membranes

Lining the respiratory and digestive tracts to trap microbes

Neutrophils, Macrophages, Eosinophils

Phagocytic cells that engulf pathogens

Natural Killer Cells

Cells that kill anything recognized as foreign, including virus-infected and cancer cells

Interferons

Proteins produced by a host cell in response to viral invasion, recruiting Natural Killer cells and helping neighboring cells produce antiviral proteins

Complement Proteins

Proteins produced in the liver that poke holes in the cell membranes of bacteria

Inflammatory Response

Redness, heat, pain, and swelling around wounds

Pyrogens

Substances released from bacteria, viruses, and body cells that raise the body’s thermostat in the hypothalamus, causing fever

Dendritic Cells

Phagocytic cells that act as antigen-presenting cells, linking innate and adaptive immunity

Antigen

A substance or molecule recognized by the immune system as foreign

Adaptive Immunity

Immune response mediated by T and B cells

Helper T Cells (CD4)

Receive information from dendritic cells and activate cytotoxic T cells and B cells

Cytotoxic T Cells (CD8)

Directly attack infected cells

B Cells

Produce antibodies that neutralize pathogens

Antibodies

Y-shaped proteins produced by B cells that are specific for a particular antigen

Herd Immunity

Reduces transmissibility and provides a measure of protection to individuals who are not immune

Allergic Reaction

An overactivation of the immune system to something that isn’t usually harmful to the body

Histamine

The main culprit of symptoms associated with allergic reactions