Animal Defense Responses

Flashcards covering key vocabulary related to animal defense responses, including lines of defense, types of immunity, and immune system components.

Physical Barriers

The body's first line of defense, preventing foreign agents from penetrating the outer layer of the body; includes skin and mucous membranes.

Skin

A physical barrier of the first line of defense of the human body; cells filled with keratin for impenetrability and shedding to remove microbes.

Mucous Membranes

A physical barrier of the first line of defense of the human body; lines the respiratory, digestive, urinary, and reproductive systems. More vulnerable than skin.

Lysozyme

Enzyme found in saliva and tears that kills bacteria by rupturing their cell walls, a chemical barrier of the first line of defense.

Phagocytes

Defensive cells of the second line of defense that engulf pathogens, damaged tissues, or dead cells (e.g., neutrophils and macrophages).

Eosinophils

Defensive cells of the second line of defense that discharge destructive enzymes to destroy pathogens too big for phagocytes (e.g., parasitic worms).

Natural Killer Cells

Defensive cells of the second line of defense that seek out abnormal cells (e.g., cancer cells).

Interferon

A defensive protein of the second line of defense that infected cells produce to protect other cells from viral infection by stimulating the production of antiviral proteins.

Complement System

A defensive protein of the second line of defense involved in pathogen destruction, enhancement of phagocytosis, stimulation of inflammation, and chemotaxis.

Inflammation

A series of events that occurs when body tissues are injured/damaged, causing redness, heat, swelling, and pain.

Fever

An abnormally high body temperature caused by pyrogens, which can help fight bacterial infections.

Immunity

Protection from infections.

Immune System

The cells and molecules responsible for immunity.

Immune Response

The collective and coordinated response of the immune system to a foreign substance.

Inborn Immunity

A genetic predisposition to immunity received from parents and ancestors.

Acquired Immunity

Immunity obtained when exposed to antigens, either naturally or artificially.

Naturally Acquired Immunity

Immunity acquired when a person is exposed to a live pathogen, develops the disease, and becomes immune as a result of the primary immune response.

Artificially Acquired Immunity

Immunity acquired through a vaccine containing antigens.

Antibodies/Immunoglobulins

Proteins produced from circulating lymphocytes that recognize and bind to an antigen, leading to the destruction of the antigen.

Vaccination

Process of introducing an attenuated or weakened antigen in a susceptible host.

Sweat-

produced by glands in the skin wash away microbes and their acidity slows bacterial growth

Mucous membranes

produce sticky mucous that traps many microbes

Saliva and tearrs

contain an enzyme called lysozyme that kills bacteria by rupturing their cell walls

cerumen (ear wax)

produced in the ear canal and protects the canal by trapping dirt and dust particles

opsonization

enhancement of phagocytosis

chemotaxis

attracting machrophages and neutrophils

IgG

Promotes opsoniza tion, neutralization, and cross-linking of antigens; less effec tive in activation of complement system than IgM

IgA

Provides localized defense of mucous membranes by cross-linking and neutralization of antigens

IgM

Promotes neutraliza tion and cross linking of antigens; very effective in complement system activation

IgE

Triggers release from mast cells and basophils of hista mine and other chemicals that cause allergic reactions

IgD

Acts as antigen receptor in the antigen-stimulated proliferation and differentiation of B cells (clonal selection