5 



Fertilization 



A. Definition of fertilization 



B. Historical considerations concerning gametic fusion and its significance. 



C. Types of egg activation 



1. Natural activation of the egg 



2. Artificial activation of the egg 



a. Object of studies in artificial parthenogenesis 



b. Some of the procedures used in artificial activation of the egg 



c. Results obtained by the work on artificial parthenogenesis 



D. Behavior of the gametes during the fertilization process 



1. General condition of the gametes when deposited within the area where fertiliza- 

 tion is to occur 



a. Characteristics of the female gamete 



1 ) Oocyte stage of development 



2) Inhibited or blocked condition 



3) Low level of respiration 



4) Loss of permeability 



b. Characteristics of the male gamete 



2. Specific activities of the gametes in effecting physical contact of the egg with the 

 sperm 



a. Activities of the female gamete in aiding sperm and egg contact 

 1) Formation of egg secretions which influence the sperm 



a) Fertilizin complex 



b) Spawning-inducing substances 



b. Activities of the male gamete in aiding the actual contact of the two gametes 



1 ) Sperm secretions 



a) Secretions producing lysis 



b) Secretions related specifically to the fertilization reactions 



c) Secretions which induce the spawning reaction in the female 



2) Relation and function of sperm number in efi'ecting the contact of the sperm 

 with the egg 



3) Influences of the seminal plasma in eff'ecting sperm contact with the egg 



4) Roles played by specific structural parts of the sperm in effecting contact 

 with the egg 



a) Role of the flagellum 



b) Role of, the acrosome in the egg-sperm contact 



5) Summary of the activities of the egg and sperm in bringing about the pri- 

 mary or initial stage of the fertilization process, namely, that of egg and 

 sperm contact 



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