Immunology: Nonspecific Chemical Defenses

A temporary increase in body temperature above normal (37°C) due to the presence of pyrogens, which are substances that trigger the hypothalamus to reset the body's thermostat to a higher set point.

Substances like bacterial toxins, antibody-antigen complexes, or products released from phagocytosed bacteria that trigger fever.

The part of the brain that regulates body temperature by acting as the body's thermostat, responding to pyrogens to reset the temperature set point.

A nonspecific immune response to tissue damage characterized by redness, swelling, heat, and pain. It helps isolate the infection, recruit immune cells, and begin the healing process.

The process by which phagocytic cells, such as macrophages and neutrophils, engulf and destroy pathogens or cellular debris.

The inherent resistance to certain diseases based on species-specific factors, like the absence of the necessary receptors for a pathogen to attach and infect.

The first line of defense against pathogens, acting as physical barriers with chemical properties like low pH, antimicrobial peptides (defensins), and lysozyme (in tears and saliva) that inhibit bacterial growth.

The helpful bacteria that reside on the skin and in the gut, outcompeting harmful microbes for resources and potentially producing substances that inhibit their growth.

A type of phagocytic cell that engulfs and destroys pathogens, presents antigens to other immune cells, and secretes signaling molecules to activate other immune responses.

The six stages of phagocytosis are: chemotaxis, adherence, ingestion, phagosome formation, fusion with lysosome, and digestion and release of debris.