Chapter 18: Diet & Health Flashcards
infectious disease
diseases caused by bacteria, viruses, parasites, or other microorganisms that can be transmitted from one person to another through air, water, or food; by contact; or through vector organisms such as mosquitoes.
antibodies
large proteins of the blood and body fluids, produced by the immune system in response to the invasion of the body by foreign molecules (usually proteins called antigens). Antibodies combine with and inactivate the foreign invaders, thus protecting the body.
antigens
substances that elicit the formation of antibodies or an inflammation reaction from the immune system. A bacterium, a virus, a toxin, and a protein in food that causes allergy are all examples of antigens.
b-cells
lymphocytes that produce antibodies. B stands for bone marrow, where the B-cells develop and mature.
cytokines
special proteins that direct immune and inflammatory responses.
immune response
the body’s reaction to foreign antigens, which neutralizes or eliminates them, thus preventing damage.
immune system
the body’s natural defense against foreign materials that have penetrated the skin or mucous membranes.
immunoglobulins
proteins capable of acting as antibodies.
lymphocytes
white blood cells that participate in acquired immunity; B-cells and T-cells.
macrophages
large phagocytic cells that serve as scavengers of the blood, clearing it of old or abnormal cells, cellular debris, and antigens.
neutrophils
the most common type of white blood cell. Neutrophils destroy antigens by phagocytosis.
phagocytes
white blood cells (neutrophils and macrophages) that have the ability to ingest and destroy foreign substances. phagein = to eat
phagocytosis
the process by which phagocytes engulf and destroy foreign materials.
t-cells
lymphocytes that attack antigens. T stands for the thymus gland, where the T-cells mature.
Name the two types of white blood cells
phagocytes
lymphocytes
Two types of immune system cells ingest and destroy foreign antigens by phagocytosis:
macrophages
neutrophils
What are the two distinct types of lymphocytes
B-cells
T-cells
What is the function of B-cells?
B-cells play a major role in resistance to infection.
They respond to infection by rapidly dividing and producing large proteins known as antibodies. Antibodies react selectively to a specific foreign organism, and the B-cells retain a memory of how to make them. The immune system can respond with greater speed the next time it encounters the same foreign organism.
What is the function of T-cells?
T-cells actively defend the body against fungi, viruses, parasites, and a few types of bacteria; they can also destroy cancer cells.
T-cells travel directly to the invasion site to battle the invaders. Recognize the antigens on surfaces of phagocytes then multiply and release cytokines to destroy all the foreign particles that have this antigen on their surfaces.
Each T-cell can attack only one type of antigen. After destroying a particular antigen, some T-cells retain the necessary information to serve as memory cells so that the immune system can rapidly produce the same type of T-cells again if the identical infection recurs.
synergistic
multiple factors operating together in such a way that their combined effects are greater than the sum of their individual effects.
synergistic
multiple factors operating together in such a way that their combined effects are greater than the sum of their individual effects.
disease and malnutrition create a synergistic downward spiral that must be broken for recovery to occur.
AIDS (acquired immune deficiency syndrome):
the late stage of HIV infection, in which severe complications of opportunistic infections and cancers develop.
HiV (human immunodeficiency virus)
the virus that destroys lymphocytes and impairs immunity, eventually causing AIDS.
What is the specific role of PROTEIN in immune function
Maintains healthy skin and other epithelial tissues (barriers to infection); participates in the synthesis and function of the organs and cells of the immune system and antibody production
What is the specific role of OMEGA 3 FATTY ACIDS in immune function
Help to resolve inflammation when it is no longer needed for the immune response through production of lipid mediators known as resolvins and protectins, which also play a role in enhancing host defense
What is the specific role of VITAMIN A in immune function
Maintains healthy skin and other epithelial tissues (barriers to infection); participates in the cell replication and specialization that supports immune-cell and antibody production and the anti-inflammatory response
What is the specific role of VITAMIN D in immune function
Regulates immune cell (T-cell) responses; participates in antibody production