MEDICAL WORK WITH MICROSCOPE 



the medical man for they are parasites of the human 

 body; many fungi, too, cause disease. A certain 

 amount of chemical \/ork with the microscope also 

 falls to the lot of the medical man. 



We have stated many times in our pages that, 

 both plants and animals, are made up of one or 

 more cells and that the cells of plants are each 

 surrounded by a more or less rigid cell wall, whilst 

 those of animals have no defmite cell wall. As a 

 start in our medical investigations we may examine 

 some cells from our own person. There is no need 

 for alarm, the operation is quite painless. After 

 having prepared our microscope and got ready a 

 clean slide, on which we place a drop of clean water, 

 we must take some clean, blunt instrument such 

 as a tooth-brush handle and gently scrape the inside 

 of the cheek. Having done so, dip the part of the 

 tooth-brush with which the scraping has been done, 

 in the drop of water, then cover the water with a 

 cover slip. 



A careful examination of our object with a fairly 

 high magnification will show that, though the 

 scraping was very gentle and quite painless, some- 

 thing has been removed from the mouth. We shall 

 see a number of cells, somewhat overlapping like 

 the tiles of a roof. They are almost colourless, and 

 have ill-defined margins, certainly no cell wall, and 

 each cell contains a dark spot near its centre. These 

 cells from our own person will give us a good idea 

 of the appearance of animal cells, for we are animals, 

 much as we may dislike the idea. The dark spot 



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