Describe the two methods of reproduction in ferns. Note ways in which they 

 are aUke and ways in which they are different. Note conditions under which 

 each takes place. Compare reproductive stages and structures of the fern with 

 those of the moss. 



QUESTIONS 



1 In what different ways do unicellular plants and animals reproduce? 



2 How does reproduction in one-celled plants and animals differ from that 

 in many-celled ones.f* 



3 In what ways do familiar plants reproduce vegetatively ? 



4 Why do we prefer to multiply many domestic varieties of plants by vege- 

 tative methods.? 



5 What different kinds of specialized reproductive cells are formed in 

 plants ? 



6 How do gametes act in reproduction.'' How do male and female gametes 

 differ from each other.? 



7 What are the relative advantages of the mammalian method of reproduc- 

 tion ? the disadvantages ? 



8 In what main groups of animals are male and female individuals distinct 

 from one another.? 



9 In what groups of organisms are individuals male and female.? 



10 In what groups of animals does the sex vary periodically or with external 

 conditions .? 



11 What are the stages in the alternation of generations in moss plants? in 

 fern plants? 



12 In what respects is reproduction in ferns more advanced than in mosses? 



13 In what groups of animals does fertilization take place within the body 

 of the female.? 



14 What are the relative advantages of fertiHzation within the body of the 

 female ? 



15 How does the number of chromosomes in the gametes compare with the 

 number in the tissue cells.? 



16 What in addition to the gametes do the gonads of the more complex 

 species produce? How do the gonads influence development.? 



17 What are the secondary sex characteristics of familiar birds and mammals? 



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