The male and female reproductive systems both produce gametes (sperm and eggs) to create offspring. The male system includes testes that produce sperm and other organs like the epididymis, vas deferens, seminal vesicles and prostate that all contribute to semen. The female system includes ovaries that produce eggs and the uterus that supports fetal development if fertilization occurs in the fallopian tubes. Both sexes develop secondary sex characteristics like body hair and voice changes in males or breast growth in females during puberty.