This short film introduces the topic of reproduction and that babies start from an egg and sperm. This series of short films ...

Once a sperm has broken through to an egg cell in order to fertilize it, the two cells need to hold together tightly. This occurs via a type of protein binding that is among the strongest in ...

LONDON — British scientists said Wednesday that they had created human sperm from embryonic stem cells for the first time, an accomplishment they say may someday help infertile men father children.