Land: 3,537,436 sq. miles (9,161,923 sq km) Water: 181,274 sq. miles (469,497 sq km) Total: 3,718,710 sq. miles (9,631,420 sq km) Land Area: (individual states) Land Area: (all countries) Horizontal Width: 2,680 miles. Vertical Length: 1,582 miles.
This intronless gene encodes a transcription factor that is a member of the high mobility group (HMG)-box family of DNA-binding proteins. This protein is the testis-determining factor (TDF), which initiates male sex determination. Mutations in this gene give rise to XY females with gonadal dysgenesis (Swyer syndrome); translocation of part of the Y chromosome containing this gene to the X chromosome causes XX male syndrome. [provided by RefSeq, Jul 2008]
FSH within the sertoli cells in the testis stimulates spermatogenesis (sperm production). Testosterone is also needed for spermatogenesis and prolongs the epididymal life, it also regulates the gonadotropin release.