From the single cell to the living, working body.
Every human being is, at the beginning, a zygote--that is to say, a single cell born of the fusion of a person's parents' germinal cells, or gametes, the ovum and the sperm. The DNA of this egg continually divides over the next nine months in order to from the tissues and organs of the body.
This initial DNA from the egg is described as "totipotent," capable of synthesizing all the proteins for all of the cell types that make up the body's tissues. But as cell divisions take place and cells become specialized (differentiated) to form ever more specialized tissues (connective, osseous, musculatory, and so on), an ever-increasing portion of the genes that are able to be expressed in the egg are no longer able to be transcribed or expressed by the specialized cells.
DNA could be compared to a gene "library," in which all of the books are initially available to be read. Over time, however, as the differentiation of tissues progresses, first entire shelves are incrementally closed off, and then, within each book, entire chapters are sealed off one after the other.
The whole organism is composed of three principal layers of tissue: the endoderm, the ectoderm, and the mesoderm. The egg division first forms the ectoderm, which then forms the other two layers, all the while respecting an anatomical gradient between internal and external. It also maintains an electric gradient: just as there is a polarization (+/-) between the inside of a cell membrane and its outer surface, there is a polarization between the layers of tissue.
The original three layers--the ectoderm, mesoderm, and endoderm--generate a total of six layers of distinct tissues. The ectoderm first differentiates the brain and nervous system tissue, then forms the endoderm, which produces the internal mucous membranes and a number of endocrine glands (such as the thyroid and the thymus) and exocrine glands (such as the pancreas).
The third layer, the mesoderm, appears between these two layers. The mesoderm forms four layers. One layer, the bones and muscles, ensure the movement of the body; two layers, one composed of the arteries and the other of the veins and lymphatic vessels, ensure the transport of blood and bodily fluids; the final layer, the connective tissue and blood cells, constitutes the internal framework of the body.
The resulting structure of the body is a precisely assembled grouping in which all the tissues are arranged between the interior and exterior.
(Extracted from Herve Janecek, Ph.D.: The Secret to Long Life in Your DNA, Healing Arts Press, 2009. www.InnerTraditions.com.)
By Herve Janecek, Ph.D.
|Printer friendly Cite/link Email Feedback|
|Title Annotation:||'The Secret to Long Life in Your DNA: The Beljanski Approach to Cellular Health' by Herve Janecek|
|Publication:||Nutrition Health Review|
|Date:||Mar 22, 2010|
|Previous Article:||Is Darwinian evolution scientific? An interview with Eugene G. Windchy.|
|Next Article:||Ray Joseph's notebook: observations on the phenomenon of youth and aging.|