Unit 7: Innate Immunity

What is innate immunity?

Nonspecific defense present at birth.

Is innate immunity specific or nonspecific?

Nonspecific.

Is innate immunity fast or slow?

Fast.

What is the first line of defense?

Physical and chemical barriers.

What are the three lines of defense?

Barriers, innate defenses, adaptive immunity.

What is the skin's main immune function?

Blocks pathogen entry.

How do mucous membranes protect the body?

Trap pathogens.

What is the function of mucus?

Traps microbes.

What do cilia do?

Sweep mucus and pathogens away.

How do tears protect the eyes?

Contain lysozyme.

What enzyme destroys bacterial cell walls?

Lysozyme.

How does saliva help immunity?

Contains lysozyme.

How does stomach acid protect the body?

Kills pathogens.

What is normal microbiota?

Helpful microorganisms on the body.

How do normal microbiota help?

Compete with pathogens.

What is a pathogen?

Disease-causing microorganism.

What is the second line of defense?

Innate internal defenses.

What is inflammation?

Response to tissue injury or infection.

What are the four signs of inflammation?

Redness, heat, swelling, pain.

What causes redness and heat?

Increased blood flow.

What causes swelling?

Increased capillary permeability.

What is the purpose of inflammation?

Destroy pathogens and begin healing.

What is vasodilation?

Widening of blood vessels.

Why does vasodilation occur?

Increase blood flow.

What is phagocytosis?

Engulfing and destroying pathogens.

What cells perform phagocytosis?

Neutrophils and macrophages.

What is the most abundant white blood cell?

Neutrophils.

What are neutrophils?

First phagocytes at infection sites.

What do monocytes become in tissues?

Macrophages.

Function of macrophages?

Phagocytosis and antigen presentation.

What are natural killer (NK) cells?

Destroy infected and cancer cells.

Do NK cells require prior exposure?

No.

How do NK cells kill cells?

Release perforin and granzymes.

What is fever?

Elevated body temperature.

Purpose of fever?

Slow microbes and boost immunity.

What protein fights viruses?

Interferons.

Function of interferons?

Block viral replication.

What is the complement system?

Group of plasma proteins.

Function of complement?

Destroy pathogens and enhance inflammation.

What is opsonization?

Coating pathogens for phagocytosis.

What is chemotaxis?

Movement toward chemicals.

Why is chemotaxis important?

Directs WBCs to infection.

What are cytokines?

Cell signaling proteins.

Function of cytokines?

Coordinate immune responses.

What is histamine?

Chemical that causes vasodilation.

Which cells release histamine?

Mast cells and basophils.

What are mast cells?

Cells that release histamine.

What do basophils release?

Histamine.

What are eosinophils best at fighting?

Parasites.

What cells respond first to bacterial infection?

Neutrophils.

Which immune response creates memory cells?

Adaptive immunity.

Does innate immunity create memory?

No.

What is the main goal of innate immunity?

Stop infection quickly.

Which immune system responds first?

Innate immunity.

Which type of immunity is the body's first response to infection?

Innate immunity.

Magic word for innate immunity?

Fast, nonspecific defense.