The Immune System: Your Body's Shield Against Harmful Invaders
The immune system is the body's natural defense mechanism that protects it against outside invaders, including bacteria, viruses, and fungi, as well as toxins. It is made up of different organs, cells, and proteins that work together to keep the body safe. This article will discuss the immune system's functions, how it works, and immune system disorders.
Understanding the Two Parts of the Immune System
There are two main parts of the immune system: the innate immune system and the adaptive immune system. The innate immune system is inherited and is present from birth, while the adaptive immune system is developed when the body is exposed to microbes or chemicals released by microbes. These two immune systems work together to protect the body.
The Innate Immune System
The innate immune system is the first to respond when it finds an invader. It is the body's rapid response system, made up of physical barriers such as the skin, the cornea of the eye, and the mucous membrane that lines the respiratory, gastrointestinal, and genitourinary tracts. These barriers protect the body against harmful germs, parasites, and cells like cancer. The cells of this immune system surround and cover the invader and kill it inside the immune system cells, known as phagocytes.
The Acquired Immune System
The acquired immune system makes cells, known as antibodies, to protect the body from a specific invader. These antibodies are developed by B lymphocytes after the body has been exposed to the invader. The antibodies stay in the body, and after the first exposure, the immune system recognizes the invader and defends against it. Immunizations train the immune system to make antibodies to protect the body from harmful diseases. The acquired immune system changes during a person's life.
The Lymphatic System: A Major Part of the Immune System
The lymphatic system is a network of lymph nodes and vessels, which carry a clear fluid called lymph. Lymph contains immune system cells, waste products, and tissue fluid. Lymph nodes are small, bean-shaped clumps of immune system cells that trap viruses, bacteria, and other invaders, including cancer cells. White blood cells are the cells of the immune system, which are made in lymph organs like the spleen or thymus, as well as in the bone marrow.
Immune System Disorders
An immune system disorder occurs when the immune system doesn't work the way it should. There are four types of immune system disorders: primary immune deficiency, acquired immune deficiency, overactive immune system, and autoimmune disease. A weak immune system that is present at birth is called primary immune deficiency. Acquired immune deficiency is when a disease weakens the immune system. An overactive immune system may cause allergic reactions to substances in the environment that are normally harmless, such as dust, mold, pollen, or foods. Autoimmune diseases occur when the immune system attacks normal, healthy tissues, and may be caused by a combination of genes and environmental factors.
