Immune System: Means Protection

– The word immune literally means “protection.
– Protection from many hazards in the environment.
– Diseases cannot be immunized, such as cancer or AIDS.
– The immune system protects against foreign substances and problems that may arise during that process.
– Cells of the immune system function to protect the individual organism against threats from anything that is foreign or nonself.
– Predominant threat to humans is infectious.
– invasion of the body by foreign organisms, viruses, bacteria, and fungi.
– Potential to cause disease.
– Disease results when cells tissues have been damaged so much that they can no longer function properly.
– Without an immune system, humans would certainly die from infectious diseases.
– The immune system also provides long-term resistance, or immunity, to reinfection by organisms that have been previously encountered.
– Once the immune system has encountered a foreign material, it quickly and efficiently responds to subsequent exposures to the same material.
– Cell-mediated immunity.
– Immune protection by antibody protein antibody-mediated immunity.
– Phagocytosis destruction of foreign material they engulf and destroy a wide variety of molecules, particles, and organisms, in contrast to antibodies, which are specific for only one antigen.
– Phagocytosis is an important part of a protective process called inflammation.
– Tissue damage such as cuts, splinters, and infectious organisms.
– Other nonspecific mechanisms include physical and biochemical barriers.
– The skin and mucous cilia antibacterial enzymes found in saliva, sweat is biochemical barriers to many microorganisms.
– Basic characteristics of immunity were recognized more than 2000 years ago.
– Certain diseases could be avoided by inducing immunity with vaccines that induce specific immunity without causing disease.
– White blood cells known as lymphocytes travel individually in the blood circulation.
– Also, collect in specialized lymphoid tissues and organs.