Human Body Defenses and Inflammation

Flashcards covering key vocabulary related to human body defenses and inflammation.

Human Body Defenses

Physiological mechanisms protecting against infection by pathogens.

Pathogens

Microorganisms that can cause disease

Innate Defenses

Defenses present from birth; respond non-specifically to pathogens.

Surface Barriers

The skin and mucous membranes lining passageways with external openings.

Internal Defenses

Quick-acting defenses that eliminate pathogens. Includes phagocytes, natural killer cells, antimicrobial proteins, inflammation, and fever.

Phagocytes

White blood cells that engulf and digest pathogens.

Antimicrobial Proteins

Proteins that kill bacteria or inhibit their growth.

Adaptive Defenses

Defenses that develop over time and target specific pathogens. Involves lymphocytes (B and T cells) and memory cells.

Lymphocytes

Specialized white blood cells; B cells produce antibodies, T cells mediate cellular immunity.

Memory Cells

Remember pathogens and mount rapid responses upon re-exposure.

Skin

Hard barrier against bacteria; has secretions (sebum, sweat) that inhibit bacterial growth.

Lysozyme

Enzyme in tears and saliva that pokes holes in bacterial cell walls, causing them to burst.

Mucus-lined membranes

Traps pathogens in the respiratory tract.

Iron-binding protein

Protein that takes iron and hides it away from bacteria, inhibiting their growth.

Inflammation

Non-specific response to infection or injury, causing redness, swelling, heat, pain, and loss of function.

Inflammation

The body's response to injury or infection; a non-specific innate defense response.

Functions of Inflammation

Limits spread of pathogens, stimulates immune response, removes debris, and sets stage for tissue repair.

Inflammation Location

Inflamed muscle does not mean muscle cells are inflamed, but rather the inflammatory process is occurring in the surrounding areolar connective tissue

Mast Cell

Key cell for inflammation; releases inflammatory chemicals (e.g., histamine).

Vasodilation

Increases blood flow to the injured area.

Hyperemia

Increased blood flow to an area.

Increased Capillary Permeability

Capillaries become more leaky, allowing fluid to leak into the interstitial space.

Chemotaxis

Chemical signal attracting white blood cells to the area of infection.

Emigration

White blood cells sneak out of the blood into the surrounding tissue.

Phagosome

Vesicle containing the microbes that are engulfed by the phagocyte.

Lysosome

Cell organelle with lots of digestive enzymes and a low pH inside of it.