Transportation or tne Gametes (Sperm and E^^) from 



tne Germ Glands to tne Site Wnere Fertilization 



Normally Occurs 



A. Introduction 



1. Activities of the male and female gametes in their migration to the site of 

 fertilization 



B. Transportation of the sperm within the male accessory reproductive structures 



1. Transportation of sperm from the testis to the external orifice of the genital duct 

 in the mammal 



a. Possible factors involved in the passage of the seminal fluid from the testis to 

 the main reproductive duct 



1) Accumulated pressure within the seminiferous tubules 



2) Activities within the efferent ductules of the testis 



b. Movement of the semen along the epididymal duct 



1 ) Probable immotility of the sperm 



2) Importance of muscle contraction, particularly in the vas deferens 



3) Summary of factors which propel the seminal fluid from the testis to the 

 external orifice of the reproductive duct in the mammal 



2. Transportation of sperm in other vertebrates with a convoluted reproductive duct 



3. Transportation of sperm from the testis in vertebrates possessing a relatively simple 

 reproductive duct 



C. Transportation of sperm outside of the genital tract of the male 



1. Transportation of sperm in the external watery medium 



2. Transportation of sperm in forms where fertilization of the egg is internal 



a. General features relative to internal fertilization 



1 ) Comparative numbers of vertebrates practicing internal fertilization 



2) Sites or areas where fertilization is effected 



3) Means of sperm transfer from the male genital tract to that of the female 



b. Methods of sperm transport within the female reproductive tract 



1 ) When fertilization is in the lower or posterior portion of the genital tract 



2) When fertilization occurs in the upper extremity of the oviduct 



3) When fertilization occurs in the ovary 



D. Sperm survival in the female genital tract 



E. Sperm survival outside the male and female tracts 



1. In watery solutions under spawning conditions 



2. Sperm survival under various artificial conditions; practical application in animal 

 breeding 



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