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"Article Summery" Name: "Immunity and the Invertebrates" Periodical: Scientific Pages Read: 9 The complex immune systems of humans and other mammals evolved over quite a long time - in some rather surprising ways. In 1982 a Russian zoologist named Elie Metchniko ....

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.... They gained further insight into how immunity works. The most basic requirement of an immune system is to distinguish between one's own cells and "non-self" cells. The second job is to eliminate the non- self cells. When a foreign object enters the body, several things happen. Blood stops flowing, the immunity system begins to eliminate unwanted microbes with phagocytic white blood cells. This defensive mechanism is possessed by all animals with an innate system of immunity. Innate cellular immunity is believed to be the earliest form of immunity. Another form of innate immunity is complement, composed of 30 different proteins of the blood. ....