Tabular comparison of spermatogenesis and oogenesis
A tabular comparison of spermatogenesis and oogenesis furnishes evidence for major differences in the timing of production, number and size of gametes.
|Number of gametes|
|Principle: continuous production.
Although from puberty to old age sperm cells are constantly being engendered, the production is subject to extreme fluctuations regarding both quantity and quality.
|Principle: Using up the oocytes generated before birth.
Continual decrease of the oocytes, beginning with the fetal period.
Exhaustion of the supply at menopause.
|Four functioning, small, motile spermatozoids at the end of the meiosis||One large, immotile oocyte and three shriveled polar bodies are left at the end of the meiosis|
|No meiotic divisions.||Entering into meiosis (arrested in the dictyotene stage)|
|No germ cell production.||Production of the entire supply of germ cells.|