II. 



THE CELL. 

 A. Simple Cells. 



Material. A prepared slide showing large cells. 

 Apparatus. A compound microscope. 



Study first with a low power and then with a high power 

 a prepared slide showing large cells, as the cells of the cast- 

 off skin of a newt, that have been stained. 



Notice : 



I. A SINGLE CELL. 



a. Its general shape. 



b. The protoplasm, lightly stained. 



c. The nucleus, deeply stained. 



d. The nucleolus, a dark spot in the nucleus. 



e. Deeply stained loops, or chromatin loops, may be scat- 

 tered through the protoplasm. This is the part that is 

 thought to bear the hereditary characteristics. 



/. The cell-wall, when present, on the outside of the cell. 



II. THE ARRANGEMENT OF THE CELLS. 



a. What is the general arrangement ? 



b. Are there any spaces between the cells ? 



c. Sketch several cells and label all the parts. 



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