GROWTH AND REPRODUCTION 45 



terms are common to both botany and zoology, the same being true of 

 another term, zygote, which is apphed to the cell resulting from the union 

 of a sperm cell and an egg cell in fertilization. This union of two sex 

 cells is also known as syngnmy. This sexual type of reproduction is 

 characteristic of higher animals, while asexual reproduction, which is any 

 type not involving these sex cells, occurs chiefly in lower ones. 



