The distinction between Somatic and Germ cells

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The distinction between Somatic and Germ cells Our bodies have evolved to carry out that one function as successfully as possible. However, most cells will do so only in a supporting role, they are not themselves destined to be transmitted. As geneticists, we draw a distinction between the germ cells which provide the continuity of life from one generation to the next, and the somatic cells which are all the rest. When a sperm fertilises an egg to create a zygote , the embryo begins to develop. Initially all the cells are capable of giving rise to any part of the embryo or its extraembryonic tissues. However, after about 6 or 7 divisions, some cells have become irreversibly programmed to give rise only to a subset of possible cell or tissue types and this process of irreversible differentiation
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Unformatted text preview: continues until all the organs have been constructed. During this process, a small number of progenitor germ cells are sequestered until rudimentary gonads (testes or ovaries) have formed when the germ cells migrate into them. At this stage germ cells are neither sperm nor egg cells, they are precursers, spermatogonia or oogonia. In their own way they are every bit as differentiated as any other (somatic) cell of the body. There is no way that a spermatogonium will ever be able to differentiate into a liver cell for instance. However, the germ cells contain the potential to be transmitted to the next generation and contribute one half of the DNA of the next individual....
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