The immune system
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The immune system

1. The immune system



The immune system is the system of specialized
cells and organs that protects an organism from
outside biological influences.


When the immune system is functioning properly, it
protects the body against bacteria and viral infections
and destroys cancer cells and foreign substances.


The immune system is often divided into
two sections:
• Innate immunity: Comprised of hereditary (always there)
components that provide an immediate "first-line" of defense to
continuously ward off pathogens.
• Acquired immunity: By
manufacturing a class of
proteins called antibodies,
and by producing Tcells specifically designed to
target particular pathogens,
the body can develop a
specific immunity to
particular pathogens.


Another way of categorizing this is
"nonspecific defenses" (skin, mucous membranes,
phagocytes, fever, interferons, cilia, and stomach acid)
and "specific defenses" (the cell-mediated and the
humoral systems, both of which attack specific


Many factors can contribute to the general
weakening of the immune system:
• Unbalanced diet
• Alcohol abuse
• Drug abuse
• Medications (particularly the
use of anti-cancer drugs,
corticosteroids, and antibiotics)
• Radiation
• Cigarette smoke
• Stress
• Age - Ability of the immune system to respond is
decreased at early and old age.
• Diseases
• Inadequate sleep at the Delta brain wave level.
• Lack of exercise as well as excessive exercise resulting.


The most important function of the human immune system
occurs at the cellular level of the blood and tissues.
Each white blood cell type (B-cells, T-cells, natural killer cells,
and macrophages) has a different responsibility, but all function
together with the primary objective of recognizing, attacking,
and destroying bacteria, viruses, cancer cells, and all substances
seen as foreign.


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