Innate Immunity: Nonspecific Host Defenses

Practice flashcards based on the lecture notes about innate immunity and nonspecific host defenses.

What is the definition of immunity?

The ability of the body to ward off disease caused by microorganisms and to protect from environmental agents.

What are the two types of immunity?

Innate immunity and adaptive immunity.

What is the first line of defense in the body?

The skin, which serves as a physical barrier.

What are mucus membranes?

Epithelial layers with underlying connective tissue that secrete mucus to prevent entry of some microorganisms.

What is the role of the lacrimal apparatus?

Cleanses the eyes.

What is perspiration's function in innate immunity?

Flushes the skin and contains lysozyme to help combat microbial growth.

What are resident microbiota?

Microorganisms that establish residence in the body and prevent the overgrowth of harmful pathogens.

What occurs in the second line of defense?

Defensive cells, inflammation, fever, and antimicrobial substances come into play.

What are erythrocytes?

Red blood cells.

What is the function of neutrophils?

Phagocytosis and highly motile to enter infected tissue.

What do basophils produce?

Histamine, which creates inflammation and allergic responses.

What is the role of eosinophils?

Production of toxin proteins, especially in parasitic infections.

What is the function of macrophages?

Phagocytosis; they mature from monocytes after leaving the bloodstream.

What is phagocytosis?

The ability of a cell to completely ingest another cell.

What happens during inflammation?

It is a localized response characterized by pain, redness, swelling, and heat.

What is the significance of cytokines in inflammation?

They trigger inflammatory responses and recruit more inflammatory cells.

What is fever in terms of innate immunity?

A systemic response with an abnormally high body temperature that enhances the immune response.

What is the complement system?

A system of proteins produced by the liver that aids the immune system in destroying pathogens.

What are interferons?

Cytokines that play a major role in fighting viral infections by signaling neighboring cells to produce antiviral defenses.