Tne Development or tne Gametes or Sex Cells 



A. General considerations 



B. Controversy regarding germ-cell origin 



C. Maturation (differentiation) of the gametes 



1. General considerations 



2. Basic structure of the definitive sex cell as it starts to mature or differentiate 

 into the male meiocyte (i.e., the spermatocyte) or the female meiocyte (i.e., the 

 oocyte) 



3. Nuclear maturation of the gametes 



a. General description of chromatin behavior during somatic and meiotic mitoses 



b. Reductional and equational meiotic divisions and the phenomenon of cross- 

 ing over 



c. Stages of chromatin behavior during the meiotic prophase in greater detail 



1) Leptotene (leptonema) stage 



2) Zygotene or synaptene (zygonema) stage 



3) Pachytene (pachynema) stage 



4) Diplotene (diplonema) stage 



5) Diakinesis 



d. Peculiarities of nuclear behavior in the oocyte during meiosis; the germinal 

 vesicle 



e. Character of the meiotic (maturation) divisions in the spermatocyte compared 

 with those of the oocyte 



1 ) Dependent nature of the maturation divisions in the female meiocyte 



2) Inequality of cytoplasmic division in the oocyte 



f. Resume of the significance of the meiotic phenomena 



4. Cytosomal (Cytoplasmic) maturation of the gametes 



a. General aspects of the cytoplasmic maturation of the gametes 



b. Morphogenesis (spermiogenesis) (spermioteleosis) of the sperm 



1 ) Types of sperm 



2) Structure of a flagellate sperm 



a) Head 



b) Neck 



c) Connecting body or middle piece 



d) Flagellum 



3) Spermiogenesis or the differentiation of the spermatid into the morphologi- 

 cally differentiated sperm 



a) Golgi substance and acroblast; formation of the acrosome 



b) Formation of the post-nuclear cap 



c) Formation of the proximal and distal centrioles; axial filament 



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