Immunity is the ability to resist infection or to counter the harmful toxins produced by infecting organisms ("Immunity" A Dictionary of Biology, 2008). An immune system response is produced by Antibodies and white blood cells, which are the defensive cells in our body. Natural immunity or innate/inherited immunity is the body’s first defense in controlling invading organisms during the early stages of infection. The white blood cells in our body, also known as phagocytic macrophages can identify and respond to viruses, fungi, bacteria, and parasites (antigens). When our body encounters and of these intruders macrophages surround the microorganism and secrete cytokines (regulatory proteins) and chemokines, which attract more immune cells (neutrophils and monocytes) from blood vessels to the site and cause inflammation. When we encounter an infection or illness caused by viruses, bacteria, parasites, or fungi the complement system of defense proteins is activated. These proteins coat targeted cells with fragments that assist macrophages in recognizing bacteria, viruses, parasites, and fungi.
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