Immunity Summary: Innate and Adaptive Responses

Vocabulary-style flashcards covering key innate and adaptive immunity concepts from Page 1 notes.

Immunity

The body's defense system against pathogens, with innate (non-specific) and adaptive (specific) components.

Innate immunity

Inborn, non-specific defense system; provides immediate protection and includes first and second lines of defense.

First line of defense

Mechanical barriers that prevent pathogen entry, mainly skin and mucous membranes.

Skin

Outer protective barrier of the first line of defense.

Mucous membranes

Moist linings that trap pathogens and are part of the first-line barriers.

Second line of defense

Non-specific defenses including chemical barriers, inflammation, phagocytosis, fever, and NK cells.

Chemical defenses

Non-specific antimicrobial substances that hinder pathogens.

Inflammation

Non-specific tissue response to injury or infection, with redness, heat, swelling, and pain.

Phagocytosis

Process by which phagocytes engulf and digest pathogens.

Fever

Systemic increase in body temperature as part of the immune response.

NK cells

Natural killer cells; innate lymphocytes that destroy virus-infected or abnormal cells.

Neutrophils

Phagocytic white blood cells that respond early to infection.

Macrophages

Large phagocytes that engulf pathogens and present antigens to T cells.

Mast cells

Cells that release histamine and other mediators during inflammation.

Fibroblasts

Connective tissue cells that produce extracellular matrix and participate in defense and tissue repair.

Epithelial cells

Cells forming protective surfaces; contribute to defense by barrier function and antimicrobial secretions.

Adaptive immunity

Also called acquired immunity; specific immune response involving T- and B-cells.

3rd line of defense

The adaptive immune response involving T- and B-cells.

T-cells

Lymphocytes that mediate cell-mediated immunity; include helper, cytotoxic, regulatory, and memory subsets.

B-cells

Lymphocytes responsible for humoral (antibody-mediated) immunity; differentiate into plasma and memory cells.

Cell-mediated immunity

Adaptive immunity driven by T-cells against infected or abnormal cells.

Helper T-cells

T-cells that assist other immune cells by releasing cytokines.

Cytotoxic T-cells

T-cells that kill infected or abnormal cells.

Regulatory T-cells

T-cells that modulate immune responses to prevent autoimmunity.

Memory T-cells

Long-lived T-cells that respond rapidly upon re-exposure to antigen.

Humoral immunity

Antibody-mediated immunity produced by B-cells and plasma cells.

Plasma cells

Differentiated B-cells that secrete antibodies.

Memory B-cells

Long-lived B-cells that provide rapid antibody responses on re-exposure.