The meiosis is of three types, depending on the stage where it occurs. The main difference between these three types of meiosis is, in gametic meiosis the process of meiosis occurs during the formation of gametes and results in haploid gametes formation. In zygotic meiosis the process of meiosis occurs in a zygote and again results in haploid individuals. In sporic meiosis, the division occurs during sporogenesis and results in the formation of haploid number of spores. So all theses three types of meiotic divisions depend upon the place and time of the occurrence of process of meiosis.
What is Gametic Meiosis?
Gametic meiosis occurs in gametes, during their formation and eventually give result to the formation of haploid number of gametes. Then theses gametes fuse together in the process of fertilization and give rise to zygote. It has a diplontic life style. This zygote then undergo mitosis and is converted to an individual. In sexually reproducing organisms, this type of meiosis take place during the formation of gametes and then in transfer of those gametes to the formation of a zygote.
What is Zygotic Meiosis?
Meiotic division here, occurs in a zygote. In this process the formation of a haploid individual takes place. Zygote is divided which results in haploid organisms, having haplontic life cycle unlike diplontic life cycle in gametic meiosis. In lower plants, zygotic meiosis takes place. It takes place when the zygote is about to germinate and therefore the plant or filament is haploid in nature. The resultant zygote after the process of conjugation is diploid. It undergoes a period of rest and then finally germinates. At the time of germination, meiosis occurs to form four spores.
What is Sporic Meiosis?
This type o division occurs during the process of sporogenesis and results in the formation of haploid spores. Spore divides to form gametophyte which eventually form gametes. A diploid sporophyte is formed as a result of fusion of those gametes. It has a diplohaplontic life cycle and is common in plants. Sporic meiosis also occurs in the life cycle of ferns and mosses.
- Gametic meiosis have diplontic life style. Zygotic meiosis have haplontic life cycle and sporic meiosis have diplohaplontic life cycle.
- Gametic meiosis occurs in gametes, zygotic in a zygote and sporic during sporogenesis.
- Gametic meiosis give rise to gametes, zygotic gives rise to zygote and sporic give rise to spores.
- Gametic meiosis occurs in sexually reproducing organisms.