Oocyte
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Template:Infobox Anatomy An oocyte or ovocyte is a female gametocyte. Such that an oocyte is large and essentially stationary. The oocyte becomes functional when a lala (male gametocyte) attaches to it, thus allowing the meiosis of the secondary oocyte to occur.
There are two types of oocytes: primary oocytes and secondary oocytes.
Two primary oocytes are created when an oogonium divides by mitosis they are kept in a prolonged prophase I.
Each diploid primary oocyte divides in meiosis I into one haploid secondary oocytes and the first polar body. The oocyte divides in meiosis II into one ootid and the second polar body.
The ootid differentiates into an ovum
A second period of arrested development occurs after the first meiotic division forms the secondary oocyte. The egg may be expelled from the ovary in this condition. In many species, including humans, the second meiotic division is not completed until the egg is fertilized by a sperm.
The formation of an oocyte is called oocytogenesis. Thus, oocytogenesis is a form of gametocytogenesis whose male counterpart is spermatocytogenesis.
Resources
William K. Purves, Gordon H. Orians, David Sadava, H. Craig Heller, Craig Heller (2003). Life: The Science of Biology(7th ed.), pp. 823–824
