Barriers remain, but it may be time to talk about human cloning.
The reproductive system is a collection of organs found in both sexes that work together for the purpose of producing offspring. Check here for the latest news related to the reproductive system, including fertility treatments and potential new technologies for having children.
While barnacles have extra-long penises to transfer sperm to other stationary barnacles, they broadcast sperm to reproduce with more distant mates
Determining which categories an organism falls into is no easy matter. In general, physical characteristics determine grouping.