Chapter 2
Electromagnetic Characteristics of the Human Body
2.1 Human Body Composition
The elements of the human body can be classified into different levels such as the atom, molecule, cell, tissue, and internal organs. When the human body is exposed to an external electromagnetic field, its electromagnetic characteristics are generally treated at the celluar or tissue level.
At the cellular level, electrical properties of the human body are characterized by the cell membrane and the conductive intracellular fluid and extracellular fluid. The cell membrane consists of a phospholipid bilayer with embedded proteins, and separates the interior of the cell from the outside environment. Although the membrane thickness is 10 nm at most, both its resistance and capacitance are large. Since life originated from the sea, the extracellular fluid has a composition similar to that of seawater. The composition of the intracellular fluid is about 20% protein and this is where metabolic activity occurs. The electrical properties change according to the intracellular fluid composition.
On the other hand, the resistance of the extracellular fluid is considered to be smaller than that of the intracellular liquid. The cells unite in the extracellular fluid to compose tissue. The tissue is therefore roughly distinguishable according to the method of uniting so that the electrical properties of the human body can also be characterized by the different moisture content and composition at the tissue ...