The president’s executive order signaled an intention to narrowly define the sexes, but experts say he is oversimplifying the ...

How do behavior, morphology and physiology act in concert to improve a male's reproductive success - and why is there so much variation among outcomes within and between species? Aa Aa Aa ...

Male and female reproductive systems allow human reproduction ... giving insight to the human body and its capabilities. BBC Teach has thousands of free, curriculum-linked resources to help ...

Your reproductive organs produce the sex cells that make a ... uterus and the vagina And inside a male as well as the testicles or testes, there is the sperm duct. The human reproductive system ...

President Trump issued an executive order declaring that the U.S. government would only recognize a person’s sex assigned at birth.