Properties |
Spermatogenesis |
Oogenesis |
Definition |
The production of sperms from spermatogonia is called spermatogenesis. |
The production of eggs from oogonia is called oogenesis. |
Oogenesis |
Occurs in male |
Occurs in female |
Growth phase |
Too short |
Prolonged |
Formation |
Seminiferous tubules of testis |
In ovaries |
Process |
Production of sperms from spermatogonia |
Production of ovum from oogonia |
Cell Division |
All spermatogonia are divided by meiosis, producing sperms all the times. |
Some of the oogonia divide during the production of eggs, one at a time. |
Continuity |
Spermatogenesis is a continuous process, occurring after the puberty till death. |
Early stages of the oogenesis occurs during the fetal period. The rest of the process occurs after the puberty. Only one ovum is produced per month until menopause. |
Production of ovum from oogonia |
Continuous, occurs after the puberty till death |
Discontinuous, occurs after the puberty until menopause |
Nuclear condensation |
Found |
Absent |
Sertoli cells |
Sertoli cells are found in the germinal cell epithelium, supporting the germinal cells. |
No Sertoli cells are found in the germinal cell epithelium. |
Food reserve |
Sperm contains less food reserve |
Ovum contain a lot of food reserve |
Stages |
All stages occurs inside the testis |
Except the last stage which occurs in oviduct, all stages occurs inside the ovary |
germ line epithelium |
Involved in gamete production |
Not involved |
Location |
Occurs entirely in testes |
Occurs mostly in ovaries |
Meiotic Division |
Equal division of cells |
Unequal division of cytoplasm |
Primary Gametocyte |
Primary spermatocyte is divided by meiosis 1, forming two secondary spermatocytes. |
Primary oocyte is divided by meiosis 1, forming a secondary oocyte and one polar body. |
Secondary Gametocyte |
Secondary spermatocyte is divided by meiosis 2, forming two spermatids. |
Secondary oocyte is divided by meiosis 2, forming ovum and one polar body. |
Cytokinesis |
Equal |
Unequal |
Number of gametes produced |
4 |
1 (plus 2 -3 polar bodies) |
Size of gametes |
Sperm smaller than spermatocytes |
Ova larger than oocytes |
Duration |
Uninterrupted process |
In arrested process |
Onset |
beings at puberty |
Begins in foetus (pre-natal) |
Release |
continuous |
Monthly from puberty (menstrual cycle) |
Initiation of process |
Begins at puberty |
Begins even before birth |
Motility |
Sperm are motile |
Ovum is immotile |
Starting cells |
Start from a primary spermatocyte |
Start from a primary oocyte |
Result |
Forms four motile male gametes i.e. sperms |
Forms one non-motile female gamete i.e. ovum |
Releasing |
Sperms are released from the testis |
Oocytes are released from the ovary which matures later |