Innate and Adaptive Immunity: Body Defenses and Cell Types

What is the immune system's primary function?

To protect the body by resisting or eliminating harmful foreign invaders or abnormal cells.

What are the main targets of the immune system?

Pathogenic bacteria and viruses.

What is virulence?

The disease-producing power of a pathogen.

What are leukocytes?

White blood cells that act as the effector cells of the immune system.

What are the main types of leukocytes?

Neutrophils, eosinophils, basophils, monocytes, and lymphocytes.

What do neutrophils do?

Engulf and destroy bacteria; their granules contain antimicrobial proteins.

What is the role of eosinophils?

Involved in allergic conditions and parasitic infections; they can attach to parasites and secrete substances to kill them.

What do basophils synthesize and store?

Histamine and heparin, which are involved in allergic reactions and fat particle removal from blood.

What are monocytes known for?

They are professional phagocytes that mature into macrophages and engulf damaged cells.

What is innate immunity?

A rapid, nonspecific response to foreign material that works immediately upon exposure.

What triggers inflammation?

Nonspecific responses to foreign invasion or tissue damage, involving resident tissue macrophages.

What are the steps involved in producing inflammation?

Release of chemotaxins, vasodilation, increased capillary permeability, and recruitment of leukocytes.

What is the role of interferon?

Inhibits multiplication of viruses in most cells and provides nonspecific resistance to viral infections.

What are natural killer (NK) cells?

Lymphocyte-like cells that destroy virus-infected cells and cancer cells on first exposure.

What is the complement system?

A group of plasma proteins that destroy foreign cells and can activate inflammation.

What are the two pathways of complement activation?

The alternate pathway and the classical pathway.

What is the function of the skin in the immune system?

Acts as a barrier and contains immune cells that participate in defense against pathogens.

What do keratinocytes produce?

Keratin, which helps protect the skin and synthesizes vitamin D.

What is the role of melanocytes?

Produce melanin to absorb UV rays and prevent tissue damage.

What are Langerhans cells?

Immune cells in the skin that help in immune defense.

What is chronic inflammation?

Occurs when the triggering agent persists long-term, either not eliminated or constantly present.

What are nonsteroidal anti-inflammatory drugs (NSAIDs) used for?

To suppress inflammation.

What is the significance of cytokines in inflammation?

They act as signaling molecules to recruit and activate other immune cells.

What is the role of mast cells in inflammation?

Secrete histamine, which causes vasodilation and increases capillary permeability.

What is the function of the hypodermis?

Anchors the skin to underlying muscle or bone and contains fat.

What is the primary role of adaptive immunity?

To customize defenses for specific pathogens.

What is hemopoiesis?

The process of blood cell production originating from pluripotent stem cells in the red bone marrow.