Gametogenesis - wikipedia Gametogenesis Jump to : navigation , search Not to be confused with Gametocytogenesis . Part of a series on Sex Biological terms Sexual dimorphism Male Female Sexual differentiation Feminization Virilization Sex - determination system XY X0 ZW Z0 Temperature - dependent Haplodiploidy Heterogametic sex Homogametic sex Sex chromosome X chromosome Y chromosome Testis - determining factor Hermaphrodite Sequential hermaphroditism Intersex Sexual reproduction Evolution of sexual reproduction Anisogamy Isogamy Germ cell Meiosis Gametogenesis Spermatogenesis Oogenesis Gamete spermatozoon ovum Fertilization External fertilization Internal fertilization Sexual selection Plant reproduction Sexual reproduction in animals Sexual intercourse Human reproduction Fungal reproduction Sexuality Plant sexuality Animal sexuality Human sexuality Mechanics Differentiation Activity Sex portal Biology portal Gametogenesis is a biological process by which diploid or haploid precursor cells undergo cell division and differentiation to form mature haploid gametes . Depending on the biological life cycle of the organism , gametogenesis occurs by meiotic division of diploid gametocytes into various gametes , or by ( ( mitosis mitochondrial For example , plants produce gametes through mitosis in gametophytes . The gametophytes grow from haploid spores after sporic meiosis . The existence of a multicellular , haploid phase in the life cycle between meiosis and gametogenesis is also referred to as alternation of generations . Contents ( hide ) 1 In Animals 1.1 Stages 1.1. 1 Common path 1.1. 2 Individual path 1.2 In vitro gametogenesis 2 In gametangia 3 In flowering plants 4 Meiosis 5 See also 6 References 7 Notes In animals ( edit ) Scheme showing analogies in the process of maturation of the ovum and the development of the spermatids , following their individual pathways . The oocytes and spermatocytes are both gametocytes . Ova and spermatids are complete gametes . In reality , the first polar body typically dies without dividing . Animals produce gametes directly through meiosis in organs called gonads ( testicles in males and ovaries in females ) . Males and females of a species that reproduces sexually have different forms of gametogenesis spermatogenesis ( male ) oogenesis ( female ) Stages ( edit ) However , before turning into gametogonia , the embryonic development of gametes is the same in males and females . Common path ( edit ) Gametogonia are usually seen as the initial stage of gametogenesis . However , gametogonia are themselves successors of , primordial germ cells ( PGCs ) from the dorsal endoderm of the yolk sac migrate along the hindgut to the gonadal ridge . They multiply by mitosis , and , once they have reached the gonadal ridge in the late embryonic stage , are referred to as gametogonia . Once the germ cells have developed into gametogonia , they are no longer the same between males and females . Individual path ( edit ) From gametogonia , male and female gametes develop differently - males by spermatogenesis and females by oogenesis . However , by convention , the following pattern is common for both : Cell type ploidy / chromosomes in humans DNA copy number / chromatids in human Process gametogonium diploid ( 2N ) / 46 2C before replication , 4C after / 46 before , 46 X 2 after gametocytogenesis ( mitosis ) primary gametocyte diploid ( 2N ) / 46 2C before replication , 4C after / 46 before , 46 X 2 after gametidogenesis ( meiosis I ) secondary gametocyte haploid ( N ) / 23 2C / 46 gametidogenesis ( meiosis II ) gametid haploid ( N ) / 23 C / 23 gamete haploid ( N ) / 23 C / 23 In vitro gametogenesis ( edit ) In vitro gametogenesis ( IVG ) is the technique of developing in vitro generated gametes , i.e. , `` the generation of eggs and sperm from pluripotent stem cells in a culture dish . '' This technique is currently feasible in mice and will likely have future success in humans and nonhuman primates . In gametangia ( edit ) Fungi , algae , and primitive plants form specialized haploid structures called gametangia , where gametes are produced through mitosis . In some fungi , such as the Zygomycota , the gametangia are single cells , situated on the ends of hyphae , which act as gametes by fusing into a zygote . More typically , gametangia are multicellular structures that differentiate into male and female organs : antheridium ( male ) archegonium ( female ) In flowering plants ( edit ) In angiosperms , the male gametes ( always two ) are produced inside the pollen tube ( in 70 % of the species ) or inside the pollen grain ( in 30 % of the species ) through the division of a generative cell into two sperm nuclei . Depending on the species , this can occur while the pollen forms in the anther ( pollen tricellular ) or after pollination and growth of the pollen tube ( pollen bicellular in the anther and in the stigma ) . The female gamete is produced inside the embryo sac of the ovule . Meiosis ( edit ) Meiosis is a central feature of gametogenesis , but the adaptive function of meiosis is currently a matter of debate . A key event during meiosis is the pairing of homologous chromosomes and recombination ( exchange of genetic information ) between homologous chromosomes . This process promotes the production of increased genetic diversity among progeny and the recombinational repair of damage in the DNA to be passed on to progeny . To explain the adaptive function of meiosis ( as well as of gametogenesis and the sexual cycle ) , some authors emphasize diversity , and others emphasize DNA repair See also ( edit ) Microgametogenesis References ( edit ) ^ Jump up to : Cohen , Glenn ; Daley , George Q. ; Adashi , Eli Y. ( January 11 , 2017 ) . `` Disruptive reproductive technologies '' . Science Translational Medicine . 9 ( 372 ) . doi : 10.1126 / scitranslmed. aag2959 . Retrieved January 16 , 2017 . In vitro gametogenesis ( IVG ) -- the generation of eggs and sperm from pluripotent stem cells in a culture dish . Currently feasible in mice , IVG is poised for future success in humans and promises new possibilities for the fields of reproductive and regenerative medicine . Jump up ^ Harrison CJ , Alvey E , Henderson IR ( 2010 ) . `` Meiosis in flowering plants and other green organisms '' . J. Exp . Bot. 61 ( 11 ) : 2863 -- 75 . doi : 10.1093 / jxb / erq191 . PMID 20576791 . Jump up ^ Mirzaghaderi G , Hörandl E ( 2016 ) . `` The evolution of meiotic sex and its alternatives '' . Proc. Biol. Sci. 283 ( 1838 ) . doi : 10.1098 / rspb. 2016.1221 . PMC 5031655 . PMID 27605505 . Notes ( edit ) Jump up ^ Sources are mixed when using this system of numbering . Some sources use the chromatid number when writing `` n '' rather than the ploidy number . Hence gametogonium and primary gametocyte would be `` 4n '' rather than `` 2n '' with `` 4c '' for copies . The system used below has been determined by wikipedia consensus and should not necessarily be used as the definitive source on the issue . ( hide ) Human physiology of sexual reproduction Menstrual cycle Menarche Menstruation Follicular phase Ovulation Luteal phase Gametogenesis Spermatogenesis ( spermatogonium spermatocyte spermatid sperm ) Oogenesis ( oogonium oocyte ootid ovum ) Germ cell ( gonocyte gamete ) Human sexual behavior Sexual arousal Sexual intercourse Masturbation Erection Orgasm Ejaculation Insemination Fertilisation / Fertility Implantation Pregnancy Postpartum period Mechanics of sex Life span Prenatal development / Sexual dimorphism / Sexual differentiation ( Feminization Virilization ) Puberty ( Gonadarche Pubarche Menarche Spermarche Adrenarche ) Maternal age / Paternal age Climacteric ( Menopause Late - onset hypogonadism ) Tanner scale Egg Ovum Oviposition Oviparity Ovoviviparity Vivipary Reproductive endocrinology and infertility Hypothalamic -- pituitary -- gonadal axis Hypothalamic -- pituitary -- prolactin axis Andrology Hormone Breast Thelarche Breast development Lactation Breastfeeding Retrieved from `` https://en.wikipedia.org/w/index.php?title=Gametogenesis&oldid=819447105 '' Categories : Developmental biology Reproductive system Germ cells Talk Contents About Wikipedia Беларуская Български Català Čeština Deutsch Español Français Հայերեն Bahasa Indonesia Italiano ქართული Қазақша Кыргызча Latviešu Lietuvių Македонски Nederlands Polski Português Română Русский Slovenščina Српски / srpski ไทย Українська 中文 Edit links This page was last edited on 9 January 2018 , at 12 : 18 . 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where does the formation of gametes take place
Part of a series on Sex Biological terms Sexual dimorphism Male Female Sexual differentiation Feminization Virilization Sex - determination system XY X0 ZW Z0 Temperature - dependent Haplodiploidy Heterogametic sex Homogametic sex Sex chromosome X chromosome Y chromosome Testis - determining factor Hermaphrodite Sequential hermaphroditism Intersex Sexual reproduction Evolution of sexual reproduction Anisogamy Isogamy Germ cell Meiosis Gametogenesis Spermatogenesis Oogenesis Gamete spermatozoon ovum Fertilization External fertilization Internal fertilization Sexual selection Plant reproduction Sexual reproduction in animals Sexual intercourse Human reproduction Fungal reproduction Sexuality Plant sexuality Animal sexuality Human sexuality Mechanics Differentiation Activity Sex portal Biology portal Part of a series on Sex Biological terms Sexual dimorphism Male Female Sexual differentiation Feminization Virilization Sex - determination system XY X0 ZW Z0 Temperature - dependent Haplodiploidy Heterogametic sex Homogametic sex Sex chromosome X chromosome Y chromosome Testis - determining factor Hermaphrodite Sequential hermaphroditism Intersex Sexual dimorphism Male Female Sexual differentiation Feminization Virilization Sex - determination system XY X0 ZW Z0 Temperature - dependent Haplodiploidy Heterogametic sex Homogametic sex Sex chromosome X chromosome Y chromosome Testis - determining factor Hermaphrodite Sequential hermaphroditism Intersex Sexual dimorphism Male Female Male Female Sexual differentiation Feminization Virilization Feminization Virilization Sex - determination system XY X0 ZW Z0 Temperature - dependent Haplodiploidy XY X0 ZW Z0 Temperature - dependent Haplodiploidy Temperature - dependent Sex chromosome X chromosome Y chromosome X chromosome Y chromosome Testis - determining factor Hermaphrodite Sequential hermaphroditism Sequential hermaphroditism Sexual reproduction Evolution of sexual reproduction Anisogamy Isogamy Germ cell Meiosis Gametogenesis Spermatogenesis Oogenesis Gamete spermatozoon ovum Fertilization External fertilization Internal fertilization Sexual selection Plant reproduction Sexual reproduction in animals Sexual intercourse Human reproduction Fungal reproduction Evolution of sexual reproduction Anisogamy Isogamy Germ cell Meiosis Gametogenesis Spermatogenesis Oogenesis Gamete spermatozoon ovum Fertilization External fertilization Internal fertilization Sexual selection Plant reproduction Sexual reproduction in animals Sexual intercourse Human reproduction Fungal reproduction Evolution of sexual reproduction Anisogamy Isogamy Anisogamy Isogamy Gametogenesis Spermatogenesis Oogenesis Spermatogenesis Oogenesis Gamete spermatozoon ovum spermatozoon ovum Fertilization External fertilization Internal fertilization External fertilization Internal fertilization Sexual reproduction in animals Sexual intercourse Human reproduction Fungal reproduction Sexual intercourse Human reproduction Fungal reproduction Sexuality Plant sexuality Animal sexuality Human sexuality Mechanics Differentiation Activity Plant sexuality Animal sexuality Human sexuality Mechanics Differentiation Activity Human sexuality Mechanics Differentiation Activity Mechanics Differentiation Activity Sex portal Biology portal Sex portal Biology portal Gametogenesis is a biological process by which diploid or haploid precursor cells undergo cell division and differentiation to form mature haploid gametes . Depending on the biological life cycle of the organism , gametogenesis occurs by meiotic division of diploid gametocytes into various gametes , or by ( ( mitosis mitochondrial For example , plants produce gametes through mitosis in gametophytes . The gametophytes grow from haploid spores after sporic meiosis . The existence of a multicellular , haploid phase in the life cycle between meiosis and gametogenesis is also referred to as alternation of generations . Animals produce gametes directly through meiosis in organs called gonads ( testicles in males and ovaries in females ) . Males and females of a species that reproduces sexually have different forms of gametogenesis spermatogenesis ( male ) oogenesis ( female ) spermatogenesis ( male ) oogenesis ( female ) However , before turning into gametogonia , the embryonic development of gametes is the same in males and females . Gametogonia are usually seen as the initial stage of gametogenesis . However , gametogonia are themselves successors of , primordial germ cells ( PGCs ) from the dorsal endoderm of the yolk sac migrate along the hindgut to the gonadal ridge . They multiply by mitosis , and , once they have reached the gonadal ridge in the late embryonic stage , are referred to as gametogonia . Once the germ cells have developed into gametogonia , they are no longer the same between males and females . From gametogonia , male and female gametes develop differently - males by spermatogenesis and females by oogenesis . However , by convention , the following pattern is common for both : Cell type ploidy / chromosomes in humans DNA copy number / chromatids in human Process gametogonium diploid ( 2N ) / 46 2C before replication , 4C after / 46 before , 46 X 2 after gametocytogenesis ( mitosis ) primary gametocyte diploid ( 2N ) / 46 2C before replication , 4C after / 46 before , 46 X 2 after gametidogenesis ( meiosis I ) secondary gametocyte haploid ( N ) / 23 2C / 46 gametidogenesis ( meiosis II ) gametid haploid ( N ) / 23 C / 23 gamete haploid ( N ) / 23 C / 23 Cell type ploidy / chromosomes in humans DNA copy number / chromatids in human Process gametogonium diploid ( 2N ) / 46 2C before replication , 4C after / 46 before , 46 X 2 after gametocytogenesis ( mitosis ) primary gametocyte diploid ( 2N ) / 46 2C before replication , 4C after / 46 before , 46 X 2 after gametidogenesis ( meiosis I ) secondary gametocyte haploid ( N ) / 23 2C / 46 gametidogenesis ( meiosis II ) gametid haploid ( N ) / 23 C / 23 gamete haploid ( N ) / 23 C / 23 In vitro gametogenesis ( IVG ) is the technique of developing in vitro generated gametes , i.e. , `` the generation of eggs and sperm from pluripotent stem cells in a culture dish . '' This technique is currently feasible in mice and will likely have future success in humans and nonhuman primates . Fungi , algae , and primitive plants form specialized haploid structures called gametangia , where gametes are produced through mitosis . In some fungi , such as the Zygomycota , the gametangia are single cells , situated on the ends of hyphae , which act as gametes by fusing into a zygote . More typically , gametangia are multicellular structures that differentiate into male and female organs : antheridium ( male ) archegonium ( female ) antheridium ( male ) archegonium ( female ) In angiosperms , the male gametes ( always two ) are produced inside the pollen tube ( in 70 % of the species ) or inside the pollen grain ( in 30 % of the species ) through the division of a generative cell into two sperm nuclei . Depending on the species , this can occur while the pollen forms in the anther ( pollen tricellular ) or after pollination and growth of the pollen tube ( pollen bicellular in the anther and in the stigma ) . The female gamete is produced inside the embryo sac of the ovule . Meiosis is a central feature of gametogenesis , but the adaptive function of meiosis is currently a matter of debate . A key event during meiosis is the pairing of homologous chromosomes and recombination ( exchange of genetic information ) between homologous chromosomes . This process promotes the production of increased genetic diversity among progeny and the recombinational repair of damage in the DNA to be passed on to progeny . To explain the adaptive function of meiosis ( as well as of gametogenesis and the sexual cycle ) , some authors emphasize diversity , and others emphasize DNA repair