Definition of Y chromosome

1. Atrial Fibrillation Slideshow Pictures
2. Bad Bugs and Their Bites Slideshow
3. Understanding Ulcerative Colitis Slideshow

Y chromosome: The sex chromosome that is found, together with an X chromosome, in most normal males. The Y chromosome contains the unique male-determining gene and the male fitness genes that are active only in the testis and are responsible for the formation of sperm. Other genes on the Y chromosome have counterparts on the X chromosome, are active in many body tissues, and play crucial 'housekeeping' roles with the cell.