THE CELL 93 



I must here explain to the reader more about the repro- 

 ductive cells of plants and animals, how they differ from 

 those cells that build the body. They are called germ 

 cells and as you remember, the male cell is called the sper- 

 matozoon and the one that comes from the female is called 

 the egg. However, the reader must not forget that the 

 egg and spermatozoon are cells, in every way just alike, 

 except that they are built and prepared to perform differ- 

 ent kinds of work and for that reason, they look different. 

 The egg or female cell is prepared to just sit and wait for 

 this spermatozoon with food for both to last them until 

 they can be connected with the nourishment from the 

 body. The spermatozoon is built with a powerful pro- 

 peller with which he is enabled to push his way through 

 obstacles and obstructions in a mad competitive race with 

 thousands of others, who all start at the same time in 

 search for the same object, the female cell. This act of 

 the spermatozoon and female cell meeting and joining is 

 called fertilization. You remember that the nucleus, 

 which always contains the same number of specifically 

 skilled crowds of workers, always divides exactly in two 

 whenever the cell reproduces itself or multiplies by divi- 

 sion. Now it is also a singular fact that the cell from the 

 female and also from the male discharge just half of the 

 specifically skilled crowd of workers in the nucleus, which 

 are called chromosomes, so that when the male and 

 female cells get together and find each other, and the two 

 join together to form one cell, the two together will be 

 a complete cell, and will have a full number of specifically 

 skilled workers, and the correct number of chromosomes. 

 The body cells or cells that build the body are called 

 somatic cells, and are always a little different from the 

 germ cells. Whenever these cells, which build the body, 

 begin their task, as a liver cell, or muscle cell, they 



