The X and Y chromosomes, commonly referred to as the sex chromosomes, are one such pair. They determine the biological sex, reproductive organs, and sexual characteristics that develop in a person.

Players will finally be returning to the Kalos region sometime this year, so there has never been a better time to replay ...

Why are the human sex chromosomes called “X” and “Y,” while the other 22 chromosomes are identified only by numbers? The answer begins in the late 1800s, when insect gonad cells, whose large ...

A study led by bioengineers at the University of California San Diego sheds new light on how a type of heart valve disease, called aortic valve stenosis, progresses differently in males and females.