Surface Structure-Other Than Cell Walls

SURFACE STRUCTURE - OTHER THAN CELL WALLS 

Cell has argyrome system (silverline system). Cell has perilemma. 

Acetic acid is produced from complex basal medium (eg., peptone-yeast extract broth). 

KETO- AND HYDROXY- ACIDS Any form of lactic acid 024294 024330 

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Transmission electron microscopy (TEM) is primarily used to examine the internal structure of biological samples. It can be used, however, to reveal certain surface characteristics that may otherwise be difficult to view by other types of microscopic methods. The thickness of cell wall, which could be related to the physiological or growth condition of the cell, can be best revealed by ultra-thin sections and TEM, which provides higher resolution than light microscopy (Fig. 14). The roughness of the surface can also be examined in detail, although at two-dimensional level. 

The alveolar epithelium eonsists of two major cell types. It covers a total surface area of approximately 140 in humans (7). Ninety-three pereent of the surface area (human, baboon, and rat 68), or even more (dog, rabbit, hamster, mouse, and other species 69) is covered by the squamous type I eells, and 7% or less by the cuboidal type II eells. The structural basis for the gas exehange is the interalveolar septum, whieh forms the wall between two alveoli. In this location air and blood come into close eontact, and they are separated by a tissue barrier with an average thickness of only 2 pm (human 7). Over large areas in humans and in many other speeies (69) the thickness is even less than 1 pm. 

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