Spermatogenesis and Oogenesis – Best 10 Difference

May 8, 2023
Why is Difference Between Spermatogenesis and Oogenesis

Spermatogenesis and Oogenesis: Spermatogenesis and oogenesis differ primarily in that the former involves creating sperm while the latter refers to producing eggs. Gametogenesis refers to both Spermatogenesis and Oogenesis processes that produce gametes from mitotic and meioses in the gonads, producing gametes. Gamete formation differs for males than women- Spermatogenesis for the former while Oogenesis refers to gamete production during female fertilization processes.

What Is Spermatogenesis?

Fig-01: Spermatogenesis
  • Spermatogenesis refers to the formation of spermatids within the male testis. This process starts from genetically diploic spermatogonia cells which undergo mitosis for mitosis-producing primary (diploid) spermatocytes from mitosis by mitosis from mitosis-produced spermatogonia; meiosis 1 will then divide this primary cell and produce two identical secondary spermatocytes which undergo meiosis 1 once completed by mitosis production of primary spermatocytes producing double meiosis 1 secondary cell from each primary cell, producing two identical secondary spermatocytes from meiosis 1.
  • One primary spermatocyte can produce four identical haploid spermatids during meiosis 2, taking approximately six weeks for each to differentiate into mature spermatozoa cells.

What Is Oogenesis?

  • Oogenesis refers to the process by which female eggs are created during embryonic development and continues well past puberty. Ovum is typically produced monthly.
  • Oogenesis begins in an ovary’s diploid oogonium. At embryonic development stages, this organ produces primary oocytes by mitosis. After puberty, these primary oocytes begin transforming into secondary haploid oocytes during meiosis 1. Later during meiosis 2, one secondary haploid oocyte transforms into another secondary ovum which becomes fertile (in both instances the cytoplasm divides unequally producing two unequal cells which become fertile). Finally, at ovulation, the secondary oocyte leaves the ovary.

What similarities exist between Spermatogenesis and Oogenesis?

  • Spermatogenesis and oogenesis both begin in an embryo with a diploic cell
  • This produces cells with haploid characteristics at their extreme ends.
  • Both processes of sexual reproduction play a pivotal role.
  • Both processes involve meiosis.
  • These processes both occur within germ cells.
  • Each process comprises three steps, Multiplication, Growth, and Maturation.

Spermatogenesis VS Oogenesis – Why are Differences?

Spermatogenesis refers to the process by which male gametes (sperms) form within male testes, while oogenesis involves creating egg cells from primary egg spermatocytes within an ovary and creating functional eggs or ova. Spermatogenesis starts from an oocyte; by comparison, Sperms have smaller cell sizes while Oocytes do not move at all; Oogenesis depends upon an initial primary egg producing functional eggs with one functionary egg for production, unlike Spermatogenesis which starts from an Oocyte. Sperms move while an Oocyte does not.

Spermatogenesis involves producing two cells with equal sizes through cytogenesis; on the other hand, during oogenesis, this process yields unbalanced cells which become anathema to each other – one beginning after puberty while one before birth; spermatogenesis happens quickly post-puberty while oogenesis has longer growth periods based on cycles.

  • Location of Spermatogenesis

Its Spermatogenesis occurs within the male testes while oogenesis takes place inside female ovaries; male sperm are produced outside while their counterparts exist inside their bodies for females.

  • Cell Divisions Involved

Spermatogenesis entails both mitosis and meiosis processes; their timing depends upon both cell numbers produced as well as any additional conditions or changes during meiosis that might come about, making each cycle unique in terms of the cells it produces.

  • Gametes produced are in number

Oogenesis only produces one haploid yolk cell for every diploid egg produced during oogenesis.

  • Timing the Process

Oogenesis begins just before conception and continues through menopause; on the other hand, spermatogenesis usually begins around puberty.

  • Number of Grate s Produced

Spermatogenic cells tend to be smaller and more motile than oogenesis cells, which tend to be larger but less mobile.

  • Quality of Gametes Produced

Spermatogenesis tends to produce higher quality sperm than egg cells for several reasons, including continuous production by male mammals throughout their lives whereas female mammals usually only give birth with one egg at birth. Spermatogenesis involves eliminating and selecting defective cells which results in a higher percentage of viable sperm; by comparison, oogenesis does not incorporate such processes which result in greater incidences of abnormal or defective egg cells being formed.

  • ChromosomeNumbers

Spermatogenesis differs from oogenesis by having different numbers of chromosomes; specifically, sperm cells contain half as many chromosomes compared to diploid egg cells while being significantly larger with organelles and cytoplasm compared to their male counterparts.

  • Hormones Involved

Hormones play a pivotal role in both spermatogenesis and oogenesis processes. Male spermatogenesis relies largely on testosterone; estrogen and progesterone play an integral part in female reproduction.


Both processes occur simultaneously for males and females at approximately the same time, though with significant variance. Both processes share similarities such as meiosis producing haploid cells, yet both display distinctive features. There are, nonetheless, significant variations.