The immune system презентация

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 T-cells 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 pathogens).

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.