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Fever

An abnormal elevation in body temperature caused by agents which induce fever, aimed at heating out and limiting the replication of pathogens.

Antipyretics

Medications taken to reduce fever, which can lower body temperature but may hinder the body’s natural infection-fighting ability.

Inflammation

A localized response to tissue injury aimed at limiting infection spread and isolating pathogens.

Four Cardinal Signs of Inflammation

Redness, Swelling/edema, Heat, Pain (with some suggesting loss of function as a fifth sign).

Neutrophils

Key cells in inflammation that destroy pathogens and debris.

Histamine

A chemical released by mast cells that causes vasodilation and increases capillary permeability, allowing leukocytes to enter damaged tissues.

First Line of Defense

The body’s initial nonspecific defense, comprising skin and mucous membranes.

Second Line of Defense

Nonspecific defense mechanisms such as inflammation.

Third Line of Defense

Specific immune response (adaptive immunity) activated if the first two defenses fail.

Specific Immunity

Characterized by specificity towards pathogens and memory for quicker future responses.

Cell-mediated Immunity

Involves T lymphocytes targeting pathogens inside cells, activating cytotoxic T cells.

Humoral Immunity

Involves B lymphocytes producing antibodies to flag extracellular pathogens for destruction.

Cytotoxic T Cells

Directly kill infected cells.

Helper T Cells

Support the function of other immune cells, including B cells.

Regulatory T Cells

Help maintain balance in the immune response.

Memory T Cells

Sustain memory of previously encountered pathogens for enhanced future responses.

Phases of Immune Response

Comprises Recognition, Attack, and Memory phases.

Antibody Structure

Produced by B cells with classes including IgA, IgG, IgM, IgE, and IgD, each serving different roles.

Active Immunity

The body’s production of antibodies in response to infections or vaccinations.

Passive Immunity

Transfer of antibodies from one source to another, either naturally (mother to baby) or artificially (antivenom).