Fun Facts

The Human Body | Immune System 

The human body is bombarded 24/7 by microbes and germ filled bacteria and it must be protected by the external defense system composed of the digestive, respiratory, and integumentary systems. This entire internal defense system is called the immune system, which consists of the white blood cells flowing through your veins and arteries constantly.

The immune system is made up of two parts: the innate immune system which you are born with, and the Adaptive system which you develop as you grow. The first to respond to invaders is the skin, eye’s cornea , and the mucous membrane linings of the respiratory, gastrointestinal and the genitourinary tracts which provide the first line of defense against microbes and parasites. The acquired immune system makes special proteins called antibodies to protect again a specific invader. After the first exposure the immune system will recognize the invader and defend against it. The cells of the immune system are made in the Adenoids, Bone marrow, Lymph nodes small bean shaped organs in the entire body connected by lymphatic vessels, lymphoid tissue in the small intestine, the Spleen ,the Thymus, and the Tonsils. This large mass of cells are constantly attacking foreign cells and infectious agents, by having either mucous membranes or small hair like projections called cilia that sweep the mucous with bacteria in it up through the throat and out our nose. Additionally the stomach lining secretes hydrochloric acid which is strong enough to kill many microbes.

The skin serves as the first mechanical barrier to infection which is why many victims of severe burns who lack this protective barrier often are infected by normally harmless bacteria. (J. Humphrey)