Sexual reproduction results in greater genetic diversity which allows species to better adapt to changing environments. Most plants are hermaphrodites with both male and female sex organs, while some plants have single-sex or separate male and female flowers. In many fish, the female lays eggs which are then fertilized externally when the male releases sperm over them. In humans, sexual maturation during puberty prepares the bodies for reproduction, and sexual intercourse allows sperm to fertilize eggs when the male ejaculates inside the female.

10. Reproduction in humans

11. The male reproductive organs

12. The female reproductive organs

15. Now for the main attraction