Chapter 6 Study Guide: Immune System, Inflammation & Wound Healing Flashcards

Vocabulary flashcards covering the body's lines of defense, immune system cells, innate vs. adaptive responses, mast-cell mediators, vascular changes, and the complement system based on Chapter 6 study guide notes.

First line of defense

Natural barriers including physical, mechanical, biochemical, and microbiome defenses that prevent microorganisms from entering or establishing infection.

Second line of defense

Inflammation, a rapid, nonspecific response in vascularized tissue that helps contain injury or infection and remove pathogens and debris.

Third line of defense

Adaptive immunity, a specific acquired response involving lymphocytes and immunologic memory.

Lysozyme

A biochemical barrier present in saliva, tears, sweat, and mucus that attacks bacterial cell walls.

Collectins

Antimicrobial peptides that help macrophages recognize and kill pathogens.

Dysbiosis

An imbalance in the microbiome that can affect digestion and immune health.

Mast cells

Primary cellular initiators of inflammation found near blood vessels, nerves, skin, lungs, and gut that release inflammatory mediators.

Macrophages

Primary cellular initiators developed from monocytes that engage in phagocytosis, debris removal, and inflammatory mediator release.

Neutrophils

Early inflammatory cells that arrive about 6–12 hours after injury, ingest bacteria, remove dead cells/debris, and contribute to pus.

Eosinophils

Cells that defend against parasites and help regulate vascular mediators.

Basophils

Rare leukocytes participating in allergic reactions and inflammation that release histamine and produce leukotrienes.

Dendritic cells

Phagocytic cells that migrate to lymphoid tissue and interact with T lymphocytes.

B lymphocytes

Adaptive immunity cells associated with antibody-based/humoral responses.

T lymphocytes

Adaptive immunity cells associated with cell-mediated responses.

Innate immunity

A rapid, nonspecific defense that includes natural barriers and inflammation using cellular and chemical defenses.

Adaptive (acquired) immunity

A specific acquired response using lymphocytes, including antibody-based and cell-mediated responses, providing immunologic memory.

Degranulation

The rapid release of preformed chemical stored mediators from mast cells.

Synthesis (mast cell)

The production of new lipid-derived mediators by mast cells after activation.

Histamine

A preformed mediator causing vasodilation, increased vascular permeability, increased blood flow, and contribution to inflammation/allergic responses.

Neutrophil chemotactic factor

A preformed mast-cell mediator that attracts neutrophils to the inflammatory site.

Eosinophil chemotactic factor of anaphylaxis (ECF-A)

A preformed mast-cell mediator that attracts eosinophils to the inflammatory site.

H1 receptor

A histamine receptor that mediates bronchoconstriction and vascular inflammation.

H2 receptor

A histamine receptor that stimulates gastric acid secretion and suppresses leukocyte activity.

Leukotrienes

Synthetic lipid-derived mast-cell products with effects similar to histamine, particularly important during later stages of inflammation.

Prostaglandins

Synthetic mast-cell products with effects similar to leukotrienes that induce pain.

Platelet-activating factor (PAF)

A synthetic mast-cell product with effects similar to leukotrienes that activates platelets.

Diapedesis

The movement of leukocytes through the vessel wall into tissue.

C3a and C5a

Complement components that stimulate mast-cell degranulation and histamine release.

C5a

A complement component that acts as a chemotactic factor for leukocytes.

C3b

A complement component that promotes opsonization, helping phagocytes recognize pathogens.

Membrane attack complex (MAC / C5b–C9)

A complement complex formed by C5b–C9 that creates pores in pathogen membranes, causing lysis.