Composition of the Human Body

Table 1.4 shows a distribution of the major elements found in the earth s crust, the ocean water, and the human body. The composition of the human body, which is reason-... 

As indicated in chapter 3.6., the time required for the cremation process depends mainly on the structure and chemical composition of the human body, but to a significant extent also on the construction and operation of the cremation oven. 

Biological Role of Calcium. Calcium represents a large weight fraction of the elemental composition of the human body. Of the 1.3 kg of... 

Modern science is aware of several hundred isotopes of which many are radioactive. The evolutionary process has usually used non-radioactive isotopes to define the composition of the human body. However, there are sources of natural radiation within our bodies, for example C, K, and... 

The bowel, one of the largest and most metabolically active organs, contains bacteria that may change the chemical composition of the human body. In renal failure the altered bacterial flora cause the accumulation of aliphatic amines in the gut (09, S25). Bacteria transform part of the choline in the gut to trimethylamine, which is reabsorbed and then either oxidized or demethylated to dimethylamine in the liver (S24). Dimethylamine enters the circulation and is excreted in the bile and urine. The trimethylamine and dimethylamine in the exhaled air of uremic patients may contribute to the classic fishy breath, which can be improved by hemodialysis or by gut sterilization with nonabsorbable antibiotics (S23, S25). The overall role of these compounds as uremic toxins, however, remains to be defined. 

Dahl, K., Hald, A., Jorgensen. P., Martinsen, I. and Thomassen. Y. (1990) Short and long term stability of the elemental composition of the human body fluid reference material and their use as master lots, Fresenius J. Anal. Chem. 338,526. 

Kieffer (1991) cites 37 chemical species as usually present in the elemental composition of the human body. Among them there are elements abundant in nature, such as calcium, sodium and potassium, as well as rather rare ones, such as iodine and cobalt. 

The carbon-autotrophic green plant is the primary producer of carbohydrates on the earth and uses carbohydrates extensively as storage and cell-wall substances (starch, cellulose, etc). The nitrogen-hetero-trophic animal usually consumes a rather protein-rich diet and uses proteins as supportive materials The approximate chemical composition of the human body is shown in Table 2. Most of the mass of bacteria (see Escherichia coli) is made up by proteins, which may account for 70 % of the dry weight. Numerically,... 

Table 2. Chemical composition of the human body (adapted from Rapoport). The values are rounded off. ...

Typical pH Values of Biological Materials and Foods Chemical Composition of the Human Body... 

This chapter offers a brief description of the main features of the human body and shows the areas of the body where medical textile materials may be used. The chapter describes the various systems within the human body, and analyzes the anatomical structure of the body as a whole and the skin and cell structures in detail. The physical composition of the human body is illustrated at four levels cells, tissues, organs, and systems. 

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