CHAPTER FIVE. 

 REPRODUCTION BY SPORES 



1. Another Kind of Division. In budding in yeast you 

 studied a form of division in which the protoplasm of the 

 mother cell pushed the old wall before it. This wall and 

 material became a part of the structure of the new 

 daughters. There is still another way in which the 

 protoplasm of the mother cell makes daughters. In this 

 everything takes place inside the old mother wall. It 

 does not pouch out as in the yeast nor divide into two as 

 in the bacteria. The method is called internal cell-division. 

 In such a case we have an ordinary cell, or it may become 

 very much enlarged. At the outset it may have just one 

 nucleus and the usual structures found in a cell. As the 

 cell matures and grows, the nucleus divides into two, 

 these into four, and so on until there are many small 

 nuclei lying in this single mass of protoplasm surrounded 

 by a single cell wall. 



Up to this point there may be no trace of any walls in 

 the interior. The nuclei become scattered through the 

 protoplasm. The protoplasm nearest each nucleus rounds 

 off about it. A little later each little ball of protoplasm, 

 containing one of the daughter nuclei, forms a very 

 delicate membrane about itself. We have now many 

 complete though small cells, with walls of their own, 

 inside the old parent cell wall. These small cells are 

 spores. As they ripen, the wall of the spore becomes 

 firmer, the old mother wall breaks down, and the spores 

 are thus set free. 



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