a) The human reproductive organ that produces sperms and also secretes hormone is testis. The hormone testosterone is secreted which is responsible for the development of male secondary sexual characters such as body hair, muscles and bone mass. b) i) Fertilization takes place in the oviduct.ii) Implantation of the fertilized egg takes place in the uterus. Embryo takes its nourishment from a special disc-shaped tissue embedded in the uterine wall of the mother. It is through this tissue that the nutrients and waste materials are exchanged between mother and foetus. This tissue is known as placenta.